CVE-2023-5831: Insertion of Sensitive Information Into Sent Data in GitLab

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-11-06 · updated 2026-06-17
Weakness: CWE-201

Description

An issue has been discovered in GitLab CE/EE affecting all versions starting from 16.0 before 16.3.6, all versions starting from 16.4 before 16.4.2, and all versions starting from 16.5.0 before 16.5.1 which have the `super_sidebar_logged_out` feature flag enabled. Affected versions with this default-disabled feature flag enabled may unintentionally disclose GitLab version metadata to unauthorized actors.

Affected products

GitLab: from 16.0.0 before 16.3.6; from 16.4.0 before 16.4.2; 16.5.0 — fixed in 16.3.6, 16.4.2

How to fix

Upgrade to a fixed version: GitLab 16.3.6, 16.4.2. Check the vendor advisory for mitigations.

References

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