CVE-2026-42530

Name	CVE-2026-42530
Description	NGINX Open Source has a vulnerability in the ngx_http_v3_module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This may cause a Use-after-Free in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
nginx (PTS)	bullseye	1.18.0-6.1+deb11u3	fixed
	bullseye (security)	1.18.0-6.1+deb11u8	fixed
	bookworm	1.22.1-9+deb12u6	fixed
	bookworm (security)	1.22.1-9+deb12u9	fixed
	trixie	1.26.3-3+deb13u4	fixed
	trixie (security)	1.26.3-3+deb13u7	fixed
	forky, sid	1.30.1-6	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
nginx	source	(unstable)	(not affected)

Notes

- nginx <not-affected> (Vulnerable code not present)
https://my.f5.com/manage/s/article/K000161616
https://github.com/nginx/nginx/commit/ceccdbd2ee799d020a371b9420bdacb9cf273aa7 (release-1.31.2)