CVE-2026-66357

Summary

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.

Affected Software

VendorProductVersion RangeStatus
ErlangOTP0 < 17.0unknown
ErlangOTP17.0 < 27.3.4.17affected
ErlangOTP28.0 < 28.5.0.6affected
ErlangOTP29.0 < 29.0.6affected
ErlangOTP0 < 5.10unknown
ErlangOTP5.10 < 9.3.2.7affected
ErlangOTP9.4 < 9.6.2.3affected
ErlangOTP9.7 < 9.7.2affected
ErlangOTP84adefa331c4159d432d22840663c38f155cd4c1 < *affected

Weaknesses

  • CWE-444: CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References