Missing Release of Resource after Effective Lifetime in undici - CVE-2026-18149
Published: November 3, 2026
Vulnerability identifier: #VU158710
CSH Severity: Medium
CVSS v4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-18149
CWE-ID: CWE-772
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service by accumulating pending promises and streams in applications using undici.
The vulnerability exists due to missing release of response body resources in undici's RetryHandler when a retried request receives a non-retryable response after a truncated response. A remote attacker can operate a malicious server that repeatedly returns this response sequence to leave the application's original response body pending indefinitely and cause a denial of service.
Reads such as response.body.text() hang, and bodyTimeout does not fire for the orphaned response body.
Affected software
undici
Fedora
nodejs-undici
Fedora
nodejs-undici
How to mitigate CVE-2026-18149
Install security update from vendor's website.
undici - addressed in versions 7.29.1, 8.10.2
nodejs-undici - addressed in versions 7.29.0-3.fc43, 7.29.0-3.fc44, 7.29.0-3.fc45
nodejs-undici - addressed in versions 7.29.0-3.fc43, 7.29.0-3.fc44, 7.29.0-3.fc45