How to Report IP Address Abuse: The Complete Guide to Filing Reports That Get Results

Over 90% of abuse reports never get a response. Not because the ISP does not care, but because the report was sent to the wrong address, lacked the evidence needed to take action, or was so vague that the abuse desk could not identify the offending customer. I have filed hundreds of abuse reports over the years, and the difference between one that gets results in 24 hours and one that disappears into a black hole comes down to three things: sending it to the right contact, including the right evidence, and knowing how to escalate when nothing happens.

This guide is the pillar article for a 13-part series on IP abuse reporting. It covers the full lifecycle — from identifying the responsible network, to writing a report that abuse desks actually act on, to escalating through upstream providers, Regional Internet Registries, and law enforcement when your report gets ignored. Each abuse type has a dedicated deep-dive article linked below, but this guide gives you the complete framework.

How IP Abuse Reporting Works

When you detect malicious activity from an IP address — whether it is a DDoS attack, brute force attempts, spam, phishing, or something worse — the standard recourse is to report it to the organization responsible for that IP address. This process sounds simple, but the infrastructure behind it is layered.

The Reporting Chain

The path from your report to action looks like this:

1. You detect abuse and gather evidence (logs, timestamps, traffic captures)
2. You identify the responsible network by looking up the IP's WHOIS or RDAP record
3. You send a structured report to the network's abuse contact email
4. The ISP's abuse desk receives your report, validates the evidence, and identifies their customer
5. The ISP contacts their customer, applies their acceptable use policy (AUP), and takes action — which can range from a warning to null-routing the IP to terminating the account
6. The ISP (optionally) responds to you with a resolution

Each step in this chain can fail. The most common failure points are step 2 (wrong contact) and step 3 (insufficient evidence). This guide addresses both.

WHOIS, RDAP, and the Abuse Contact Ecosystem

Every IP address on the internet is allocated by one of five Regional Internet Registries (RIRs):

These RIRs allocate IP blocks to Local Internet Registries (LIRs), which are typically ISPs and hosting providers. The WHOIS and RDAP databases maintained by these RIRs contain the abuse contact information you need.

WHOIS is the legacy protocol (RFC 3912). It returns unstructured plain text, and the format varies by RIR. Parsing abuse contacts from WHOIS output can be unreliable.

RDAP (Registration Data Access Protocol, RFC 7483) is the modern replacement. It returns structured JSON with standardized fields, including specific abuse contact roles. RDAP is what you should be using in 2025.

The critical thing to understand is that abuse contacts are not always generic. Many networks register specialized contacts for different abuse types:

• abuse@ — General abuse (the catch-all)
• security@ — Security incidents, vulnerabilities, compromised hosts
• spam@ — Unsolicited bulk email
• phishing@ — Phishing sites and emails
• copyright@ — DMCA and intellectual property complaints
• csam@ — Child sexual abuse material (highest priority, legal obligations apply)

Most WHOIS lookup tools only show you the generic abuse contact. I built DNSChkr's IP Location tool to surface all of these specialized RDAP contacts, because sending a phishing report to the copyright desk (or vice versa) often means it gets deprioritized or routed to the wrong team internally.

How to Find the Right Abuse Contact

Finding the correct abuse contact is the single most important step. A perfectly written report sent to the wrong address produces exactly zero results.

Step-by-Step Walkthrough

Here is my process for identifying the right contact:

1. Look up the IP address.

Head to DNSChkr's IP Location tool and enter the offending IP address. Below the geolocation data, you will see the WHOIS information including the network's abuse contact email. DNSChkr also surfaces specialized RDAP contacts — separate emails for copyright complaints, CSAM reports, security incidents, phishing, and spam — that most lookup tools do not show.

2. Identify the organization type.

The WHOIS output tells you who controls the IP. This is usually one of:

• Hosting provider (e.g., OVH, Hetzner, DigitalOcean) — These typically have professional abuse desks and respond within 24-72 hours
• Cloud provider (e.g., AWS, Google Cloud, Azure) — These have automated abuse pipelines and are generally fast to respond
• ISP (e.g., Comcast, Deutsche Telekom, NTT) — Response times vary wildly; residential ISPs are often slower
• Enterprise (an organization with its own IP allocation) — You may need to contact the organization directly
• Government or education (.gov, .edu networks) — Often have dedicated security teams; CERTs may also be relevant

3. Check for specialized contacts.

If you are reporting phishing and you see a phishing@ contact in the RDAP data, use that. If you are reporting spam, use the spam@ contact. For security incidents involving compromised servers, use the security@ contact. Only fall back to the generic abuse@ when no specialized contact exists.

4. Verify the network boundary.

Sometimes the WHOIS output shows a large IP block owned by a transit provider, with the actual customer allocation nested inside it. If you see something like OrgName: Cogent Communications for a /8 block, but the abuse is coming from a specific /24, dig deeper. The abuse desk may tell you "not our customer" because the /24 was reassigned. Use the most specific network registration you can find.

5. Cross-reference with DNS records.

Use the DNS Inspector to check if the IP has a PTR (reverse DNS) record. The PTR hostname often reveals the actual hosting provider. For example, a PTR of server42.hostingprovider.com tells you who to contact even if the IP block's WHOIS shows the upstream transit provider.

When WHOIS Data Is Behind Privacy Shields

Some registrations use privacy protection or show minimal data. In these cases:

• Check the RDAP response specifically (it often has more structured data than WHOIS)
• Look at the PTR record for hints about the actual provider
• Search the IP on abuse databases like AbuseIPDB — other reporters may have identified the correct contact
• Try the RIR's web interface directly (e.g., search at apps.db.ripe.net for RIPE-region IPs)
• Use the Port Scanner to check what services the IP is running — this sometimes reveals the hosting platform

Before You Report: Rule Out Legitimate Traffic

Before you spend time writing an abuse report, take five minutes to verify that the traffic you are seeing is actually malicious. I have seen sysadmins fire off reports against their own marketing team's SEO crawler, a CDN edge node, or an AI training bot that is aggressive but not abusive. These reports waste the ISP's abuse desk time and damage your credibility for future legitimate reports.

Run through this quick checklist:

1. Check the User-Agent in your access logs. The single most revealing piece of information. Legitimate crawlers identify themselves: Googlebot, AhrefsBot, GPTBot, Screaming Frog SEO Spider, etc. Use awk -F'"' '{print $6}' /var/log/nginx/access.log | sort | uniq -c | sort -rn to see all User-Agents by request count.

2. Look up the IP. Use the IP Location tool to check who owns the IP address. Does it belong to Google, Ahrefs, OpenAI, Anthropic, or another known crawling service? If the organization matches the User-Agent claim, it is almost certainly a legitimate crawler.

3. Check with your team. Is anyone in your organization running an SEO audit, site migration, or load test? Tools like Screaming Frog, Sitebulb, and Botify generate traffic patterns that look like attacks when run without IT awareness.

4. Look for AI crawlers. GPTBot, ClaudeBot, Bytespider, CCBot, and similar AI training bots can generate thousands of requests per minute. This traffic is aggressive but not malicious. The appropriate response is robots.txt or rate limiting, not an abuse report.

5. Verify reverse DNS. For search engine crawlers, run dig -x [IP] +short to get the PTR record, then verify the forward DNS matches. Genuine Googlebot resolves to *.googlebot.com, genuine Bingbot to *.search.msn.com.

If the traffic turns out to be from a legitimate crawler, the fix is robots.txt configuration or server-level rate limiting — not an abuse report. I wrote a complete guide to identifying and managing web crawlers that covers robots.txt, AI bot blocking, and the decision framework for when blocking versus reporting is appropriate.

Anatomy of an Effective Abuse Report

An abuse report needs to give the ISP's abuse desk everything they need to identify their customer, verify the abuse, and take action. Here are the seven required elements.

1. Offending IP Address (or Addresses)

State the IP address clearly. If the abuse involves multiple IPs, list all of them. Include the port numbers if relevant (e.g., the source port for DDoS traffic, or the destination port being brute-forced).

2. Timestamps in UTC

This is where most reports fail. The abuse desk needs timestamps to correlate your report with their customer's activity logs. Always use UTC to avoid timezone confusion. Include the date and time of the first observed incident and the most recent one.

Bad: "Last Tuesday afternoon" Good: "First observed: 2025-03-28T14:23:17Z, Most recent: 2025-03-28T18:45:02Z"

3. Relevant Logs

Provide the actual log evidence. Strip out anything that is not relevant to the incident, but include enough context to verify the abuse. For SSH brute force, include the auth log entries. For DDoS, include netflow or firewall logs. For spam, include the full email headers.

4. Abuse Type Classification

Clearly state what type of abuse you are reporting. Use standard terminology:

• DDoS / Denial of Service
• Brute force (SSH, RDP, FTP, etc.)
• Port scanning / network reconnaissance
• Malware distribution / botnet C2
• Compromised host
• Spam (UBE)
• Phishing
• Copyright infringement (DMCA)
• CSAM (child exploitation material)
• Fraud / scam

5. Impact Description

Explain what the abuse caused. "This IP sent SYN floods that saturated our 1Gbps uplink for 3 hours" is actionable. "This IP attacked us" is not.

6. Your Contact Information

Include your name, organization, email address, and role. Anonymous reports are less likely to get action because the abuse desk cannot follow up for clarification.

7. Attachments and Supporting Evidence

Attach packet captures (PCAP files), screenshots, full email source, or firewall rule hit counts. The more evidence you provide, the faster the abuse desk can act.

Generic Abuse Report Template

Use this template as a starting point and adapt it for the specific abuse type:

Subject: Abuse Report — [ABUSE TYPE] from [IP ADDRESS]

To: [[email protected]]

Dear Abuse Team,

I am writing to report [ABUSE TYPE] originating from IP address [IP ADDRESS]
on your network ([NETWORK NAME / ASN]).

INCIDENT DETAILS:
- Offending IP: [IP ADDRESS]
- Port(s): [SOURCE/DESTINATION PORTS if applicable]
- Abuse Type: [DDoS / Brute Force / Spam / Phishing / etc.]
- First Observed: [YYYY-MM-DDTHH:MM:SSZ]
- Most Recent: [YYYY-MM-DDTHH:MM:SSZ]
- Duration: [approximate duration]
- Target: [your IP / domain / service]
- Protocol: [TCP / UDP / ICMP / etc.]

IMPACT:
[Describe the impact — service disruption, bandwidth consumed,
accounts compromised, users affected, etc.]

EVIDENCE:
[Paste or attach relevant log excerpts, headers, or packet captures]

LOG EXCERPT:
---
[Paste sanitized log entries here, 10-20 lines maximum,
with timestamps preserved]
---

REQUESTED ACTION:
Please investigate this activity and take appropriate action under
your Acceptable Use Policy. I request confirmation that this report
has been received and a reference/ticket number for tracking.

REPORTER INFORMATION:
- Name: [Your Name]
- Organization: [Your Org]
- Email: [[email protected]]
- Role: [System Administrator / Security Engineer / etc.]
- Reference: [Your internal ticket number, if any]

Thank you for your prompt attention to this matter.

[Your Name]

Quick-Reference: Abuse Types, Contacts, and Response Times

This table maps each abuse type to the appropriate reporting destination, specialized contact type, and typical response times I have seen from major providers.

Abuse Type Deep-Dives

Each of the following sections summarizes one of the 12 abuse types covered in this series. For complete reporting procedures, evidence collection techniques, and templates specific to each type, follow the links to the dedicated articles.

DDoS Attacks

Distributed Denial of Service attacks are among the most damaging forms of IP abuse, capable of taking down entire networks by flooding them with traffic from hundreds or thousands of sources. When you are under a DDoS attack, your first priority is mitigation — activate your DDoS protection service, enable rate limiting, or contact your upstream provider for blackhole routing. Evidence collection should happen simultaneously.

For DDoS reporting, you typically need to file reports against multiple IPs, often spread across dozens of networks. Netflow data, firewall logs showing traffic volume and packet rates, and any packet captures of the attack traffic are essential evidence. Include the attack vector (SYN flood, UDP amplification, HTTP flood, etc.) and the measured impact on your bandwidth.

The most effective reports include traffic graphs showing the attack profile and reference known amplification vectors like DNS amplification when applicable. If the attack used DNS reflection, the DNS Inspector can help you verify whether the reflector IPs were running open resolvers.

Read the full guide: How to Report a DDoS Attack to an ISP

Brute Force SSH and RDP Attacks

SSH and RDP brute force attacks are the most common form of automated abuse on the internet. Botnets systematically try username/password combinations against exposed services, often hitting thousands of targets per hour from a single IP. The attacks are easy to detect — your auth logs fill up with failed login attempts — and straightforward to report.

The key evidence for brute force reports is your authentication log. On Linux, this means /var/log/auth.log or /var/log/secure. Include the failed login entries with timestamps, the usernames being attempted (this helps the ISP understand whether the attack is targeted or spray-and-pray), and the total number of attempts. Use the Port Scanner to check whether the offending IP is also probing other ports on your system.

Reports about brute force from compromised IoT devices or residential IPs tend to get slower responses because the ISP has to contact an end user rather than suspend a VPS.

Read the full guide: Report Brute Force SSH/RDP Attacks

Port Scanning and Network Reconnaissance

Port scanning sits in a legal gray area — it is not inherently illegal in most jurisdictions, and some ISPs treat it as low-priority unless it is part of a larger attack pattern. However, aggressive scanning (scanning entire subnets, high-speed SYN scans, service fingerprinting) clearly violates most acceptable use policies and is worth reporting, especially when combined with other evidence of malicious intent.

The most effective port scanning reports show a pattern of behavior: the IP scanned your network systematically, probed specific ports associated with known vulnerabilities, and possibly followed up with exploitation attempts. Firewall logs showing the scan pattern (sequential port probing, SYN-only packets, timing analysis) make for compelling evidence.

Context matters for these reports. If the same IP that scanned your ports later attempted SSH brute force, include both pieces of evidence in the same report. It transforms a "maybe just a researcher" report into a clear AUP violation.

Read the full guide: Report Port Scanning and Network Reconnaissance

Malware and Botnet Command-and-Control Traffic

Reporting malware distribution and botnet C2 servers is one of the highest-impact reports you can file. Taking down a C2 server can disrupt an entire botnet, protecting thousands of victims simultaneously. These reports get priority treatment from most abuse desks.

Evidence for C2 reports includes network traffic captures showing the communication pattern between infected hosts and the C2 server, malware samples if you have them, indicators of compromise (IoCs) like specific URLs, domain names, or unique protocol fingerprints, and references to any existing malware analysis or threat intelligence reports about the family in question.

For maximum impact, report to both the ISP's abuse desk and the relevant national CERT (Computer Emergency Response Team). CERTs coordinate takedowns across jurisdictions and often have established relationships with ISPs that accelerate the process.

Read the full guide: Report Malware and Botnet C2 Traffic

Hacked Servers and Compromised Hosts

When you detect abuse from a server that appears to have been compromised (as opposed to a purpose-built attack infrastructure), the reporting approach is slightly different. Your goal is to alert the server's owner and their ISP that the system has been compromised, so they can remediate the vulnerability and stop the abuse.

Signs that an IP is a compromised host rather than a dedicated abuse server include: it has a legitimate reverse DNS name, it hosts a real website or service, the abuse is intermittent rather than continuous, and the attack patterns are consistent with known botnet behavior. Use DNSChkr's IP Location tool to check the geolocation and hosting information — a compromised WordPress site on shared hosting looks very different from a bulletproof VPS in a known abuse-friendly data center.

Include in your report any evidence that the host is compromised, not just the abuse itself. URL paths that suggest a web shell, unusual outbound connections, or known malware signatures all help the server owner understand that they have a security problem to fix.

Read the full guide: Report Hacked Server Compromise

Spam

Spam reporting has a well-established ecosystem with dedicated blocklist operators, feedback loops, and automated processing. For email spam, the most important evidence is the full email headers — not just the From address and subject line, but the complete Received chain, SPF/DKIM/DMARC results, and Message-ID.

When reporting spam from an IP, you should report to multiple destinations: the ISP's abuse desk (use the spam@ specialized contact if available), major blocklist operators like Spamhaus, and the sender's domain registrar if the domain is being used for phishing or fraud. The IP Location tool helps you identify whether the spam is coming from a dedicated mail server, a compromised host, or a VPS that has been set up specifically for spamming.

Spam reports are most effective when they include multiple instances over a time period, showing a pattern rather than a single message. Include the full source of at least 3-5 messages.

Read the full guide: Report Spam IP Address Abuse

Phishing

Phishing reports need to go to multiple parties simultaneously: the ISP hosting the phishing site, the domain registrar, the brand being impersonated, and anti-phishing organizations like the Anti-Phishing Working Group (APWG). Speed is critical — phishing campaigns have a short active window, and every hour the site stays up means more victims.

Your report should include the phishing URL, screenshots of the phishing page, the full email used to lure victims (including headers), and details about which brand or service is being impersonated. If the phishing site is using an IP that has geolocation and hosting data visible through DNSChkr's IP Location tool, include that information to help the abuse desk quickly locate the account.

Phishing reports sent to the phishing@ specialized RDAP contact, when available, are typically routed to a dedicated team that processes takedowns faster than the general abuse queue.

Read the full guide: Report Phishing Email and Website IP

DMCA and Copyright Infringement

DMCA takedown notices have specific legal requirements under US law (17 U.S.C. 512). A valid DMCA notice must include identification of the copyrighted work, the infringing material and its location, a statement of good faith belief, a statement of accuracy under penalty of perjury, and your physical or electronic signature. Missing any of these elements gives the ISP grounds to ignore your notice.

Send DMCA notices to the ISP's designated DMCA agent — this is the copyright@ specialized contact in RDAP data, or the agent registered with the US Copyright Office. The ISP has an obligation under the DMCA safe harbor provisions to "expeditiously" remove or disable access to the infringing material upon receiving a valid notice.

For non-US jurisdictions, equivalent frameworks exist (EU Copyright Directive, UK CDPA). The report format is similar, but the legal basis and required elements differ. Check the applicable law for the hosting provider's jurisdiction.

Read the full guide: DMCA Takedown Notice Template and Copyright Reporting

Child Sexual Abuse Material (CSAM)

CSAM is the most serious category of abuse, and the reporting obligations are fundamentally different from any other type. Do not contact the ISP directly as your first step. In the United States, reports must go to the National Center for Missing and Exploited Children (NCMEC) through their CyberTipline. In the UK, report to the Internet Watch Foundation (IWF). In the EU, use the national hotline listed at inhope.org.

ISPs and hosting providers have legal obligations to preserve evidence and cooperate with law enforcement when they receive CSAM reports through proper channels. Reporting directly to the ISP's abuse desk without going through the proper legal channels can actually compromise an investigation.

If you encounter CSAM, report it immediately through the appropriate national channel, preserve any URLs or IP addresses you observed (but do not download or store the material), and then report to the ISP using the csam@ specialized contact if one exists in the RDAP record.

Read the full guide: Report Child Exploitation Material (CSAM)

Reporting to Law Enforcement

Some forms of IP abuse constitute criminal activity that should be reported to law enforcement in addition to the ISP. In the US, the FBI's Internet Crime Complaint Center (IC3) at ic3.gov handles cybercrime complaints. In the UK, Action Fraud is the primary reporting portal. Europol's EC3 handles cross-border cybercrime in the EU.

Law enforcement reports require a different level of documentation than ISP abuse reports. You need to demonstrate financial loss, quantify the impact, and provide evidence that is suitable for legal proceedings. This means chain-of-custody considerations, avoiding tampering with evidence, and providing complete, unredacted logs.

The reality is that law enforcement has limited resources and focuses on high-impact cases. Reports about DDoS attacks causing significant financial damage, organized fraud campaigns, and ransomware incidents get the most attention. A single brute force attempt is unlikely to generate a law enforcement response, but a sustained campaign with documented financial losses might.

Read the full guide: Report Cybercrime to Law Enforcement (FBI IC3)

CERT Teams

Computer Emergency Response Teams (CERTs) — also called CSIRTs (Computer Security Incident Response Teams) — coordinate incident response across organizations and sometimes across national borders. Most countries have a national CERT (US-CERT, CERT-EU, JPCERT/CC in Japan, AusCERT in Australia), and many sectors have their own (financial services, healthcare, government).

CERTs are particularly valuable when the abuse involves compromised infrastructure, advanced persistent threats, or cross-border coordination. They often have established relationships with ISPs and law enforcement that individual reporters do not have. Use the security@ specialized contact from RDAP data when reporting security incidents.

When reporting to a CERT, frame your report as a security incident rather than a complaint. CERTs want to understand the threat, not assign blame. Include technical indicators of compromise, the scope of the incident, and any threat intelligence that helps characterize the actor.

Read the full guide: Report a Security Incident to a CERT Team

Usenet Abuse

Usenet abuse — including spam, binary piracy, and excessive cross-posting — is handled through a separate reporting ecosystem that predates modern ISP abuse desks. Usenet providers have their own acceptable use policies, and the reporting conventions differ from standard IP abuse reporting.

For spam on Usenet, the traditional approach involves reporting to the Usenet provider's abuse desk and potentially to automated spam-tracking systems. For copyright infringement via Usenet binary groups, DMCA notices to the Usenet provider's designated agent are the standard approach. The same DMCA requirements apply as for web hosting.

Usenet abuse reports should identify the specific newsgroups affected, include the full article headers (including the Message-ID, Path, and NNTP-Posting-Host), and specify the volume and duration of the abuse.

Read the full guide: Report Usenet Abuse and Spam

What Happens After You File a Report

Understanding the ISP's internal process helps set expectations and informs your follow-up strategy.

Typical Processing Timeline

1. Acknowledgment (0-24 hours): Most professional abuse desks send an automated acknowledgment with a ticket number. If you do not receive one, your report may not have been received.

2. Triage (1-48 hours): The abuse desk classifies the report by severity. CSAM and active DDoS get immediate priority. Spam and port scanning go to the standard queue.

3. Investigation (24-72 hours): The abuse desk correlates your evidence with their internal logs to identify the specific customer. They may need to contact the customer to determine if the server was compromised or intentionally malicious.

4. Action (48-96 hours): Actions range from a warning email to the customer, to rate-limiting the IP, to null-routing it, to terminating the account entirely. The severity of the abuse and the customer's history determine the response.

5. Resolution (varies): Some ISPs will notify you of the action taken. Many will not, citing customer privacy. This is frustrating but normal.

Response Rates by Provider Type

In my experience, response rates vary significantly:

• Major cloud providers (AWS, GCP, Azure, DigitalOcean): 80-95% response rate within 48 hours. These companies have mature, staffed abuse desks and automated processing.
• Large hosting providers (OVH, Hetzner, Vultr): 60-80% response rate within 72 hours. Quality varies by region.
• Tier-1 ISPs (Cogent, Lumen, NTT): 40-60% response rate. They often forward reports to their downstream customers.
• Regional ISPs: 20-50% response rate. Smaller operations with less staffing.
• Bulletproof hosting providers: Near 0% response rate. These providers intentionally ignore abuse reports.

Follow-Up Cadence

If you do not receive an acknowledgment within 48 hours:

1. Day 3: Resend the original report with "FOLLOW-UP" in the subject line
2. Day 7: Send a second follow-up referencing the original timestamp
3. Day 14: Escalate to the upstream provider or RIR (see next section)

When Abuse Reports Fail: Escalation Paths

Some reports will not get results through the standard channel. Here is how to escalate.

1. Contact the Upstream Provider

Every network has at least one upstream transit provider. If the ISP hosting the abusive IP does not respond, identify their upstream and report there. The upstream provider can apply pressure — or in extreme cases, threaten to disconnect the downstream network.

To find the upstream provider, look at the BGP path for the IP's ASN. Tools like bgp.tools, PeeringDB, and Hurricane Electric's BGP toolkit show the upstream transit relationships. File your abuse report with the upstream's abuse desk, including evidence that the downstream provider failed to respond.

2. File an RIR Complaint

If the network's WHOIS data is inaccurate (no valid abuse contact, wrong email addresses, outdated information), file a complaint with the relevant RIR. Accurate registration data is a condition of receiving IP allocations, and RIRs take data accuracy seriously.

• ARIN: File via the ARIN Contact Center ([email protected])
• RIPE NCC: Use the RIPE NCC Contact Form or email [email protected]
• APNIC: Email [email protected]
• LACNIC: Email [email protected]
• AFRINIC: Email [email protected]

RIRs can require their members to update contact information, and in extreme cases, can revoke IP allocations.

3. Report to Law Enforcement

For abuse that constitutes a crime (DDoS, fraud, data theft, CSAM), file a report with the appropriate law enforcement agency. This is not an alternative to ISP reporting — do both. See the law enforcement reporting guide for jurisdiction-specific details.

4. Engage Sector CERTs

If the abuse targets or originates from a specific sector (financial services, healthcare, government), the sector CERT may be able to apply pressure that individual reporters cannot. National CERTs can also coordinate with international counterparts for cross-border abuse. Read more in the CERT team reporting guide.

5. Use Blocklist and Reputation Services

When direct reporting fails, hitting the network in their deliverability and reputation is an alternative form of pressure:

• Spamhaus — Report to their blocklist. Being listed on the Spamhaus Block List (SBL) affects the network's ability to deliver email and is a powerful motivator for ISPs.
• AbuseIPDB — Report the IP publicly. AbuseIPDB is widely used by firewall operators and automated blocking systems.
• Google Safe Browsing — Report phishing and malware URLs. Browsers will display warnings to users.
• SURBL / URIBL — Report malicious domains for blocklisting in email filters.

6. Public Disclosure (Last Resort)

In cases of systemic abuse where all other channels have failed, public disclosure through security mailing lists (like NANOG for network operators), social media, or the press can apply reputational pressure. This should be a last resort — it can burn bridges with the ISP's abuse desk and may have legal implications depending on your jurisdiction.

Tools for Building Your Evidence

Before you file a report, use these tools to build a comprehensive evidence package:

• IP Location Lookup — Identify the network, geolocation, ASN, and all abuse contacts (including specialized RDAP contacts for phishing, spam, copyright, CSAM, and security). This is your starting point for every abuse report.
• DNS Inspector — Check PTR records for the offending IP, verify domain DNS configuration, and investigate domains used in phishing or spam campaigns.
• Port Scanner — Determine what services the offending IP is running. A host running only SSH on port 22 and a botnet C2 on port 4444 tells a different story than a host running a full web stack.
• What's My IP — Confirm your own IP address to ensure you are correctly identifying the source of abuse (not accidentally reporting your own proxy or VPN egress).

Best Practices Checklist

Before sending any abuse report, run through this checklist:

• Correct abuse contact — Verified via RDAP, not guessed from domain name
• Specialized contact used — Phishing to phishing@, spam to spam@, etc.
• UTC timestamps — All times in ISO 8601 format with Z suffix
• Sanitized logs — Personal data removed except for the offending IP
• Impact quantified — Bandwidth, downtime, affected users, or financial loss stated
• Abuse type classified — Using standard terminology
• Your contact info included — Real name, email, organization
• Template used — Structured format that the abuse desk can parse quickly
• Evidence attached — Logs, PCAPs, screenshots, email headers as appropriate
• Sent to the right mailbox — Not postmaster@, not info@, but abuse@ or the specialized variant
• Copy saved — Keep a copy of every report with the timestamp you sent it

Common Mistakes That Get Your Report Ignored

Even well-intentioned reports fail when they make these mistakes:

Sending to the wrong contact. Emailing info@ or support@ instead of the abuse desk. These addresses go to customer service teams who may not forward abuse reports internally. Always use the RDAP abuse contact.

No timestamps. "This IP attacked us yesterday" is useless. The abuse desk cannot correlate your report with their logs without specific timestamps.

Threats and emotional language. "I will sue you if you don't shut this down immediately" gets your report deprioritized or ignored. Be professional and factual.

Reporting your own users. Verify that the offending IP is not one of your own addresses, a CDN edge node, or a legitimate scanner like Shodan or Censys before reporting.

Over-reporting. Sending 50 individual reports for 50 IPs in the same /24 when a single consolidated report would suffice. This clogs the abuse desk's queue and makes your reports less likely to be read.

Missing evidence. "IP 1.2.3.4 attacked us" with no logs, timestamps, or description of the attack. The abuse desk cannot act on this.

Reporting to the wrong RIR. WHOIS data for an IP allocated by RIPE will not return useful results if you query ARIN's database. Use a tool like DNSChkr's IP Location lookup that automatically queries the correct RIR.