CVE-2026-72815 go-chi CVE debrief

Who should care

Defenders responsible for systems using go-chi chi versions >= 5.2.1 and before 5.3.0 should assess exposure and apply the patch to prevent IP spoofing and bypassing of IP-based access control lists and rate-limiting mechanisms.

Why it matters

The CVE-2026-72815 vulnerability in go-chi chi allows for IP spoofing, which can lead to bypassing of security controls and potential unauthorized access or malicious activity. Defenders should prioritize verifying exposure and applying the patch.

• Bypassing IP-based access control lists
• Bypassing rate-limiting mechanisms
• Forging log entries with spoofed IP addresses
• Potential for unauthorized access or malicious activity

Technical summary

The go-chi chi versions >= 5.2.1 and before 5.3.0 contain an IP spoofing vulnerability in the RealIP middleware. The vulnerability allows a remote attacker to bypass IP-based access control lists and rate-limiting mechanisms, and forge log entries, by supplying a spoofed IP address in the X-Forwarded-For header. The issue is fixed in version 5.3.0. Defenders should prioritize verifying exposure and applying the patch, as the vulnerability allows for IP spoofing and bypassing of IP-based access control lists and rate-limiting mechanisms.

Defensive priority

Defenders should prioritize verifying exposure and applying the patch, as the vulnerability allows for IP spoofing and bypassing of IP-based access control lists and rate-limiting mechanisms.

Recommended defensive actions

• Verify if the system uses go-chi chi versions >= 5.2.1 and before 5.3.0
• Apply the patch by updating to version 5.3.0
• Review and update IP-based access control lists and rate-limiting mechanisms
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, including its description and affected versions. However, additional information on exploitation or impact is limited. The vulnerability is in the RealIP middleware. There are no known exploits, but defenders should verify exposure and apply the patch. The issue is fixed in version 5.3.0.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.