undici vulnerable to Denial of Service via unhandled exception in cache-interceptor response replay

published 2026-11-06 3d ago modified 2026-11-06 3d ago also EUVD-2026-118179

cvss: 5.9; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 23%
public exploits: 0; none known

undici is an HTTP client for Node.js. In versions 7.0.0 through 7.30.1 and 8.0.0 through 8.12.3, when the cache interceptor is composed with a downstream handler that throws during response processing (such as the built-in dump interceptor exceeding its maxSize, or the decompress interceptor rejecting more than five Content-Encoding values), a throw raised asynchronously while a cached response is replayed escapes as an uncaught exception or unhandled promise rejection and terminates the Node.js process. A malicious or compromised HTTP server can crash any such client by serving a cacheable response that triggers the throw on replay, including on a 304 revalidation of a stale entry, so the impact is availability only. The issue is fixed in undici 7.30.2 and 8.12.4, and users should upgrade to one of those versions or later. As a workaround, avoid composing the cache interceptor with a response handler that throws during response processing until upgrading.

Patch / fix

fixed in 1

undici undici 7.30.2, 8.12.4

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Exploit prediction

0.31% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

undici undici

Classification

Weakness

CWE-248 Uncaught Exception
CWE-755 Improper Handling of Exceptional Conditions

References

Sources

CVE List CVE-2026-120222
NVD CVE-2026-120222

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