# CVE-2026-73812: inets, httpd: HTTP Request Smuggling via Transfer-Encoding and Content-Length

Status: published. Published: 2026-09-01. Updated: 2026-11-11.

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, OTP 28.5.0.6, and OTP 29.0.6, corresponding to inets from 5.10 before 9.3.2.7, 9.6.2.3, and 9.7.2. Whether OTP before OTP 17.0, corresponding to inets before 5.10, is affected is unknown.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: EEF) — https://github.com/erlang/otp/commit/591dc00dc99dc2a426167a3b5257c0c94bd45e91

## Affected products and versions

- Erlang / OTP (otp): ≥ 17.0; < * (affected, otp); unaffected at 27.3.4.17; unaffected at 28.5.0.6; unaffected at 29.0.6. Source: CNA: EEF
- Erlang / OTP (inets): ≥ 5.10; < * (affected, otp); unaffected at 9.3.2.7; unaffected at 9.6.2.3; unaffected at 9.7.2. Source: CNA: EEF
- Erlang / OTP (erlang/otp): ≥ 84adefa331c4159d432d22840663c38f155cd4c1; < 591dc00dc99dc2a426167a3b5257c0c94bd45e91 (affected, git); ≥ 591dc00dc99dc2a426167a3b5257c0c94bd45e91; < * (unaffected, git). Source: CNA: EEF

## Severity and prioritization

- CVSS 4.0: 8.3 (high); CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N; source: CNA: EEF

- CISA KEV: No listing in collected sources

- EPSS: 0.52% as of 2026-11-10; percentile 44.77%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-444

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/erlang/otp/security/advisories/GHSA-7j6m-4ffg-hg46 (CNA: EEF; vendor-advisory)

- https://cna.erlef.org/cves/CVE-2026-73812.html (CNA: EEF; related)

- https://osv.dev/vulnerability/EEF-CVE-2026-73812 (CNA: EEF; related)

- https://www.erlang.org/doc/system/versions.html#order-of-versions (CNA: EEF; x_version-scheme)

- https://github.com/erlang/otp/commit/591dc00dc99dc2a426167a3b5257c0c94bd45e91 (CNA: EEF; patch)

## Provenance

- CNA: EEF: https://www.cve.org/CVERecord?id=CVE-2026-73812; retrieved 2026-11-11; source updated 2026-11-11

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-73812; retrieved 2026-11-11; source updated Not reported

Revision: 6f9e9006b4e6f6c508ef4ecfabb581abdaf41bdbdb51c05ade275556e1159513

Canonical: https://y2.dev/cve/CVE-2026-73812

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