VULNERABILITY INTELLIGENCE

CVE-2026-9658

CVSS score7.3 HIGH
EPSS probability0.23%
CISA KEVNot currently listed
Published2026-05-28
Last modified2026-10-26
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Description

Plack::Middleware::Security::Common versions before 0.13.1 for Perl did not block header injections in request paths. The header injection rule was ineffective at blocking header injections in the request paths unless they were double-encoded, for example, GET /path\r\nHTTP/1.1\r\nHost: secret.example.com Note that it is unclear whether request paths with CRLF followed by additional headers would be blocked by reverse proxies, or how they would be processed by Plack-based servers.

Weakness classification

  • CWE-113: Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')
  • CWE-790: Improper Filtering of Special Elements

Primary references