CVE-2026-23941

HIGH EPSS 40.6%
Published Mar 13, 20263mo ago · Modified May 21, 20261mo ago
7.0 CVSS 4.0
High
Find Similar
Published Mar 13, 2026 3mo ago
Last Modified May 21, 2026 1mo ago

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.

CVSS Details

Base Score
7.0
Exploitability
—
Impact
—
Vector string
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
40.6% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-444

Affected Products 6

VendorProductVersionRange
erlangerlang\/inets*≥5.10  –  <9.1.0.5
erlangerlang\/inets*≥9.3  –  <9.3.2.3
erlangerlang\/inets*≥9.6  –  <9.6.1
erlangerlang\/otp*≥17.0  –  <26.2.5.18
erlangerlang\/otp*≥27.0  –  <27.3.4.9
erlangerlang\/otp*≥28.0  –  <28.4.1

References 7

  • cna.erlef.org https://cna.erlef.org/cves/CVE-2026-23941.html
    Vendor Advisory
  • github.com https://github.com/erlang/otp/commit/a4b46336fd25aa100ac602eb9a627aaead7eda18
    Patch
  • github.com https://github.com/erlang/otp/commit/a761d391d8d08316cbd7d4a86733ba932b73c45b
    Patch
  • github.com https://github.com/erlang/otp/commit/e775a332f623851385ab6ddb866d9b150612ddf6
    Patch
  • github.com https://github.com/erlang/otp/security/advisories/GHSA-w4jc-9wpv-pqh7
    Vendor Advisory
  • osv.dev https://osv.dev/vulnerability/EEF-CVE-2026-23941
    Third Party Advisory
  • erlang.org https://www.erlang.org/doc/system/versions.html#order-of-versions
    Product

Remediation

  • github.com https://github.com/erlang/otp/commit/a4b46336fd25aa100ac602eb9a627aaead7eda18
    Patch
  • github.com https://github.com/erlang/otp/commit/a761d391d8d08316cbd7d4a86733ba932b73c45b
    Patch
  • github.com https://github.com/erlang/otp/commit/e775a332f623851385ab6ddb866d9b150612ddf6
    Patch