CVE-2026-62243

Name	CVE-2026-62243
Description	Netty (io.netty:netty-handler) versions from 4.2.0.Final through 4.2.16.Final and versions through 4.1.136.Final disable TLS hostname verification on the SslProvider.OPENSSL client path when a plain (non-extended) X509TrustManager is used and Unsafe-based trust-manager wrapping is unavailable (Java 25+). In this configuration the OpenSSL client does not perform hostname verification, allowing a man-in-the-middle attacker to present a certificate issued for a different hostname that is accepted without validation. Fixed in 4.2.17.Final and 4.1.137.Final.
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
netty (PTS)	bullseye	1:4.1.48-4+deb11u2	vulnerable
	bullseye (security)	1:4.1.48-4+deb11u3	vulnerable
	bookworm, bookworm (security)	1:4.1.48-7+deb12u2	vulnerable
	trixie (security), trixie	1:4.1.48-10+deb13u1	vulnerable
	forky, sid	1:4.1.48-16	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
netty	source	(unstable)	(unfixed)

https://github.com/netty/netty/security/advisories/GHSA-p85m-gvr3-788c