[ CVE-2026-18149 · Published 4 Sep 2026 ]
undici vulnerable to Denial of Service via orphaned RetryHandler response body
[ Description ]Official description
undici's retry handler can leave an already-exposed response body pending forever. When a server returns a successful response that declares a Content-Length, sends only part of the body, and closes the connection, the retry handler retries the request. If the retry returns a non-retryable status such as 400, the handler forwards that new response downstream and replaces its internal response stream, but the original response body that the application still holds is never ended or destroyed. As a result calls that read that body never settle, and the configured body timeout does not fire because its timer is tied to the connection parser rather than the orphaned body. An attacker-controlled server can trigger this with two short responses without keeping a connection open, and repeated requests accumulate pending promises and streams that can exhaust application concurrency or memory. This affects undici versions from 7.11.0 up to 7.29.1 and from 8.0.0 up to 8.10.2. Users should upgrade to undici 7.29.1 or 8.10.2.
[ Fixes ]Fixes and patches
- undici 7.29.1Fixed version · GitHub Advisories · npm package undici: upgrade to 7.29.1 or later (affected >= 7.11.0, < 7.29.1)
- undici 8.10.2Fixed version · GitHub Advisories · npm package undici: upgrade to 8.10.2 or later (affected >= 8.0.0, < 8.10.2)
[ Advisories ]Government CERT advisories
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CERT-FRCERTFR-2026-AVI-1336
Multiple vulnerabilities in IBM products Translated from French
Multiple vulnerabilities have been discovered in IBM products. Some of them allow an attacker to cause remote arbitrary code execution, privilege escalation and remote denial of service.
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BSI CERT-BundWID-SEC-2026-3596
IBM App Connect Enterprise: Multiple vulnerabilities Translated from German
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CERT-FRCERTFR-2026-AVI-1233
Multiple vulnerabilities in IBM products Translated from French
Multiple vulnerabilities have been discovered in IBM products. Some of them allow an attacker to cause remote arbitrary code execution, remote denial of service and a breach of data confidentiality.
[ Packages ]Affected open-source packages
- undici npmAffected >= 7.11.0, < 7.29.1 · fixed in 7.29.1 · GHSA-pmjh-fq2x-6v4x
- undici npmAffected >= 8.0.0, < 8.10.2 · fixed in 8.10.2 · GHSA-pmjh-fq2x-6v4x