CVE-2026-71380 Erlang CVE debrief

Who should care

Defenders responsible for systems using Erlang/OTP inets httpd should assess their exposure and potential impact. They should verify their current OTP and inets versions and plan to upgrade to fixed versions if necessary.

Why it matters

CVE-2026-71380 is a Missing Release of Resource after Effective Lifetime vulnerability in Erlang/OTP inets httpd that allows denial of service attacks. Defenders should verify exposure, assess impact, and plan to upgrade to fixed versions.

• Denial of service attacks are possible
• Verification of exposure and impact is necessary
• Upgrade to fixed OTP and inets versions is recommended
• Monitoring systems for potential attacks is advised

Technical summary

The vulnerability is caused by the httpd_request_handler:handle_info/2 function canceling the request timeout as soon as a parse step succeeds, which includes the headers. The clause that handles a decoder asking for more data re-arms the socket with {active, once} without setting any further timer. This allows an unauthenticated remote attacker to cause denial of service by sending valid request headers with a large Content-Length and then stalling before the body is complete.

Defensive priority

Defenders should prioritize verifying exposure and assessing the impact of this vulnerability on their systems, particularly those using Erlang/OTP inets httpd. They should check their current OTP and inets versions, and plan to upgrade to fixed versions if necessary.

Recommended defensive actions

• Verify current OTP and inets versions
• Assess exposure and potential impact
• Plan to upgrade to fixed OTP and inets versions if necessary
• Monitor systems for potential denial-of-service attacks
• 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

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, including its description, affected versions, and references to source-specific vulnerability assessments. The vulnerability is caused by the httpd_request_handler:handle_info/2 function canceling the request timeout as soon as a parse step succeeds, which includes the headers. The clause that handles a decoder asking for more data re-arms the socket with {active, once} without setting any further timer. This allows an unauthenticated remote attacker to cause denial of

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.