CVE-2026-1456: Allocation of Resources Without Limits or Throttling in GitLab

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-02-11 · updated 2026-06-17
Weakness: CWE-770

Description

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.7 before 18.7.4, and 18.8 before 18.8.4 that could have allowed an unauthenticated user to cause denial of service through CPU exhaustion by submitting specially crafted markdown files that trigger exponential processing in markdown preview.

Affected products

GitLab: from 18.7.0 before 18.7.4; from 18.8.0 before 18.8.4 — fixed in 18.7.4, 18.8.4

How to fix

Upgrade to a fixed version: GitLab 18.7.4, 18.8.4. Check the vendor advisory for mitigations.

References

https://about.gitlab.com/releases/2026/02/10/patch-release-gitlab-18-8-4-released/
https://gitlab.com/gitlab-org/gitlab/-/issues/587688
https://hackerone.com/reports/3517928

Get alerted when CVE-2026-1456 or the next vulnerability affects your stack