What’s Vulnerable › Vulnerabilities

CVE-2026-100755: Acceptance of Extraneous Untrusted Data With Trusted Data in GitLab

• Severity: medium (CVSS 4.6 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-13 · updated 2026-10-14
• Weakness: CWE-349

Description

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 16.2 before 19.2.8, 19.3 before 19.3.5, and 19.4 before 19.4.2 that, under certain deployment configurations, could have allowed an authenticated user to poison cached page content served to other users due to improper cache key construction.

Affected products

• GitLab: from 16.2.0 before 19.2.8; from 19.3.0 before 19.3.5; from 19.4.0 before 19.4.2 — fixed in 19.2.8, 19.3.5, 19.4.2

How to fix

Upgrade to a fixed version: GitLab 19.2.8, 19.3.5, 19.4.2. Check the vendor advisory for mitigations.

References

• https://docs.gitlab.com/releases/patches/patch-release-gitlab-19-4-2-released/
• https://gitlab.com/gitlab-org/gitlab/-/work_items/627507

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