CVE-2021-39947: GitLab Runner

High severity, CVSS 7.5. EPSS: 0.9% chance of exploitation in the next 30 days.

In specific circumstances, trace file buffers in GitLab Runner versions up to 14.3.4, 14.4 to 14.4.2, and 14.5 to 14.5.2 would re-use the file descriptor 0 for multiple traces and mix the output of several jobs

Affected products

• GitLab GitLab Runner: before 14.3.4 (fixed in 14.3.4); from 14.4.0, before 14.4.2 (fixed in 14.4.2); from 14.5.0, before 14.5.2 (fixed in 14.5.2)

Published 2022-06-06. Last modified 2026-06-17.