httpd function check_header/3 rejects duplicate Content-Length (per CVE-2026-23941) but never checks for the TE+CL co-presence that RFC 9112 §6.3 identifies as a probable smuggling attempt. handle_body/3 frames by chunked and silently discards Content-Length. A CL-preferring front-end paired with chunked-preferring inets creates a classic CL.TE front-end/back-end desync.
This issue affects OTP from OTP 17.0 before OTP 27.3.4.17, from OTP 28.0 before OTP 28.5.0.6, and from OTP 29.0 before OTP 29.0.6, corresponding to inets from 5.10 before 9.3.2.7, from 9.4 before 9.6.2.3, and from 9.7 before 9.7.2. Whether OTP before OTP 17.0, corresponding to inets before 5.10, is affected is unknown.
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Freebsd | — | Upgrade erlang-runtime28Upgrade erlang-runtime29Upgrade erlang-runtime27Upgrade erlang | Sep 2, 2026 | Sep 1, 2026 |
| Ubuntu | — | Upgrade erlang-megacoUpgrade erlang-inets (Ubuntu Pro)Upgrade erlang-baseUpgrade erlang-eldapUpgrade erlang-eldap (Ubuntu Pro)Upgrade erlang-sslUpgrade erlang-ssl (Ubuntu Pro)Upgrade erlang-base (Ubuntu Pro)Upgrade erlang-public-keyUpgrade erlang-base-hipe (Ubuntu Pro)Upgrade erlang-snmp (Ubuntu Pro)Upgrade erlang-inetsUpgrade erlang-megaco (Ubuntu Pro)Upgrade erlang-snmp | Sep 29, 2026 | Sep 28, 2026 |
With curated Threat Intelligence, you can see which vulnerabilities truly put you at risk, prioritize what matters most, and act before attackers do.
Explore Intelligence Hub