CRLF Injection Affecting ruby-rack package, versions *


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.04% (12th percentile)

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  • Snyk IDSNYK-DEBIAN12-RUBYRACK-15930621
  • published8 Apr 2026
  • disclosed2 Apr 2026

Introduced: 2 Apr 2026

NewCVE-2026-26962  (opens in a new tab)
CWE-93  (opens in a new tab)

How to fix?

There is no fixed version for Debian:12 ruby-rack.

NVD Description

Note: Versions mentioned in the description apply only to the upstream ruby-rack package and not the ruby-rack package as distributed by Debian. See How to fix? for Debian:12 relevant fixed versions and status.

Rack is a modular Ruby web server interface. From version 3.2.0 to before version 3.2.6, Rack::Multipart::Parser unfolds folded multipart part headers incorrectly. When a multipart header contains an obs-fold sequence, Rack preserves the embedded CRLF in parsed parameter values such as filename or name instead of removing the folded line break during unfolding. As a result, applications that later reuse those parsed values in HTTP response headers may be vulnerable to downstream header injection or response splitting. This issue has been patched in version 3.2.6.

CVSS Base Scores

version 3.1