CVE-2025-23167

Name	CVE-2025-23167
Description	A flaw in Node.js 20's HTTP parser allows improper termination of HTTP/1 headers using `\r\n\rX` instead of the required `\r\n\r\n`. This inconsistency enables request smuggling, allowing attackers to bypass proxy-based access controls and submit unauthorized requests. The issue was resolved by upgrading `llhttp` to version 9, which enforces correct header termination. Impact: * This vulnerability affects only Node.js 20.x users prior to the `llhttp` v9 upgrade.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
Debian Bugs	977716, 1105919

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
node-undici (PTS)	bookworm	5.15.0+dfsg1+~cs20.10.9.3-1+deb12u4	vulnerable
	bookworm (security)	5.15.0+dfsg1+~cs20.10.9.3-1+deb12u3	vulnerable
	trixie	7.3.0+dfsg1+~cs24.12.11-1	vulnerable
	sid	7.3.0+dfsg1+~cs24.12.11-2	vulnerable

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
llhttp	ITP					977716
node-undici	source	(unstable)	(unfixed)			1105919

Notes

[bookworm] - node-undici <no-dsa> (Minor issue)
https://nodejs.org/en/blog/vulnerability/may-2025-security-releases#improper-http-header-block-termination-in-llhttp-cve-2025-23167---medium