Summary
undici vulnerable to Denial of Service via orphaned RetryHandler response body
Advisory details
Impact
undici's RetryHandler can leave a response body pending indefinitely. When a retried request receives a non-retryable response after a truncated one, the original response.body held by the application is never settled, so reads such as response.body.text() hang and bodyTimeout does not fire. A malicious server can repeat this to accumulate pending promises and streams, leading to denial of service.
Patches
Patched in undici v7.29.1 and v8.10.2.
Workarounds
Impose an independent request deadline and destroy the response body when it expires. bodyTimeout alone does not prevent this.
References
- https://github.com/advisories/GHSA-pmjh-fq2x-6v4x
- https://github.com/nodejs/undici/security/advisories/GHSA-pmjh-fq2x-6v4x
- https://nvd.nist.gov/vuln/detail/CVE-2026-18149
- https://github.com/nodejs/undici/commit/3c6726599cea8646384dde846c97d630da472a74
- https://github.com/nodejs/undici/commit/e905b5b87e6953bcc542af90557b2fee5b7b5974
- https://hackerone.com/reports/3892751
- https://cna.openjsf.org/security-advisories.html
- https://github.com/nodejs/undici/releases/tag/v7.29.1
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