CVE-2026-18149 (GCVE-0-2026-18149)

Vulnerability from cvelistv5 – Published: 2026-09-04 17:21 – Updated: 2026-09-04 17:49
VLAI
Title
undici vulnerable to Denial of Service via orphaned RetryHandler response body
Summary
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.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-04 17:49 UTC
CWE
  • CWE-772 - Missing Release of Resource after Effective Lifetime
Assigner
openjs CNA under the redhat root
CNA scorecard C 66/100 over 142 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
undici undici Affected: 7.11.0 , < 7.29.1 (semver)
Unaffected: 7.29.1 (semver)
Affected: 8.0.0 , < 8.10.2 (semver)
Unaffected: 8.10.2 (semver)
guessed Create a notification for this product.
Credits
mcollina UlisesGascon
Show details on NVD website
To clipboard 

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