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.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Debian Fixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 1:27.3.4.1+dfsg-1+deb13u2 |
| sid | Fixed | 1:27.3.4.9+dfsg-1 |
| forky | Fixed | 1:27.3.4.9+dfsg-1 |
| bullseye | Fixed | 1:23.2.6+dfsg-1+deb11u4 |
| bookworm | Fixed | 1:25.2.3+dfsg-1+deb12u4 |
Application impact
| Vendor | Product | Versions | Fixed |
|---|---|---|---|
| erlang | erlang\/inets | {"startIncluding":"5.10","endExcluding":"9.1.0.5"} | 9.1.0.5 |
| erlang | erlang\/otp | {"startIncluding":"17.0","endExcluding":"26.2.5.18"} | 26.2.5.18 |
References
- https://github.com/erlang/otp/security/advisories/GHSA-w4jc-9wpv-pqh7
- https://cna.erlef.org/cves/CVE-2026-23941.html
- https://osv.dev/vulnerability/EEF-CVE-2026-23941
- https://www.erlang.org/doc/system/versions.html#order-of-versions
- https://github.com/erlang/otp/commit/a4b46336fd25aa100ac602eb9a627aaead7eda18
- https://github.com/erlang/otp/commit/a761d391d8d08316cbd7d4a86733ba932b73c45b
- https://github.com/erlang/otp/commit/e775a332f623851385ab6ddb866d9b150612ddf6
- https://security-tracker.debian.org/tracker/CVE-2026-23941
- https://www.suse.com/security/cve/CVE-2026-23941.html
CWEs
CWE-444
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.