Cross-site Scripting (XSS) Affecting gitlab-rails-ce-18.8 package, versions <18.8.11-r4


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.33% (24th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-GITLABRAILSCE188-18496311
  • published1 Aug 2026
  • disclosed24 Mar 2026

Introduced: 24 Mar 2026

CVE-2026-33170  (opens in a new tab)
CWE-79  (opens in a new tab)

How to fix?

Upgrade Chainguard gitlab-rails-ce-18.8 to version 18.8.11-r4 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream gitlab-rails-ce-18.8 package and not the gitlab-rails-ce-18.8 package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

Active Support is a toolkit of support libraries and Ruby core extensions extracted from the Rails framework. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, SafeBuffer#% does not propagate the @html_unsafe flag to the newly created buffer. If a SafeBuffer is mutated in place (e.g. via gsub!) and then formatted with % using untrusted arguments, the result incorrectly reports html_safe? == true, bypassing ERB auto-escaping and possibly leading to XSS. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

CVSS Base Scores

version 3.1