CVE-2026-23941

Name	CVE-2026-23941
Description	Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling') vulnerability in Erlang OTP (inets httpd module) allows HTTP Request Smuggling. This vulnerability is associated with program files lib/inets/src/http_server/httpd_request.erl and program routines httpd_request:parse_headers/7. The server does not reject or normalize duplicate Content-Length headers. The earliest Content-Length in the request is used for body parsing while common reverse proxies (nginx, Apache httpd, Envoy) honor the last Content-Length value. This violates RFC 9112 Section 6.3 and allows front-end/back-end desynchronization, leaving attacker-controlled bytes queued as the start of the next request. This issue affects OTP from OTP 17.0 until OTP 28.4.1, OTP 27.3.4.9 and OTP 26.2.5.18, corresponding to inets from 5.10 until 9.6.1, 9.3.2.3 and 9.1.0.5.
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)
Debian Bugs	1130912

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
erlang (PTS)	bullseye	1:23.2.6+dfsg-1+deb11u1	vulnerable
	bullseye (security)	1:23.2.6+dfsg-1+deb11u3	vulnerable
	bookworm	1:25.2.3+dfsg-1+deb12u3	vulnerable
	bookworm (security)	1:25.2.3+dfsg-1+deb12u1	vulnerable
	trixie	1:27.3.4.1+dfsg-1+deb13u1	vulnerable
	forky, sid	1:27.3.4.8+dfsg-1	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
erlang	source	(unstable)	(unfixed)			1130912

Notes

https://github.com/erlang/otp/security/advisories/GHSA-w4jc-9wpv-pqh7
Fixed by: https://github.com/erlang/otp/commit/a4b46336fd25aa100ac602eb9a627aaead7eda18 (OTP-28.4.1)
Fixed by: https://github.com/erlang/otp/commit/a761d391d8d08316cbd7d4a86733ba932b73c45b (OTP-27.3.4.9)
Fixee by: https://github.com/erlang/otp/commit/e775a332f623851385ab6ddb866d9b150612ddf6 (OTP-26.2.5.18)