CVE-2026-66357

Publication date 1 September 2026

Last updated 28 September 2026

Ubuntu priority

Medium

Why this priority?

Description

httpd has never implemented obs-fold (RFC 2616 §2.2 / RFC 7230 §3.2.4 header continuation lines). Every CRLF followed by a non-CRLF octet unconditionally starts a new header. This missing feature became a security concern as the understanding of HTTP request smuggling attacks evolved. 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.

Status

Package Ubuntu Release Status
erlang 26.04 LTS resolute
Fixed 1:27.3.4.6+dfsg-1ubuntu0.1
24.04 LTS noble
Fixed 1:25.3.2.8+dfsg-1ubuntu4.7
22.04 LTS jammy
Fixed 1:24.2.1+dfsg-1ubuntu0.7
20.04 LTS focal
Fixed 1:22.2.7+dfsg-1ubuntu0.5+esm2
18.04 LTS bionic
Fixed 1:20.2.2+dfsg-1ubuntu2+esm3
16.04 LTS xenial
Fixed 1:18.3-dfsg-1ubuntu3.1+esm3
14.04 LTS trusty
Fixed 1:16.b.3-dfsg-1ubuntu2.2+esm2

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Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
erlang

Severity score breakdown

CVSS version: CVSS v4.0

Base score 8.3 · High

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:L/SA:N

References

Related Ubuntu Security Notices (USN)

    • USN-8827-1
    • Erlang vulnerabilities
    • 28 September 2026

Other references

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