CVE-2023-3399: Insertion of Sensitive Information Into Sent Data in GitLab

Severity: high (CVSS 7.7 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 2026-10-28
Weakness: CWE-201

Description

An issue has been discovered in GitLab EE affecting all versions starting from 11.6 before 16.3.6, all versions starting from 16.4 before 16.4.2, all versions starting from 16.5 before 16.5.1. It was possible for an unauthorised project or group member to read the CI/CD variables using the custom project templates.

Affected products

GitLab: from 11.6.0 before 12.9.8; from 12.10.0 before 12.10.7; 13.0.0 — fixed in 12.10.7, 12.9.8
GitLab: from 11.6 before 16.3.6; from 16.4 before 16.4.2; from 16.5 before 16.5.1 — fixed in 16.3.6, 16.4.2, 16.5.1

How to fix

Upgrade to a fixed version: GitLab 12.10.7, 12.9.8; GitLab 16.3.6, 16.4.2, 16.5.1. Check the vendor advisory for mitigations.

References

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