CVE-2025-2256

Improper Validation of Specified Quantity in Input in GitLab

An issue has been discovered in GitLab CE/EE affecting all versions from 7.12 before 18.1.6, 18.2 before 18.2.6, and 18.3 before 18.3.2 that could have allowed unauthorized users to render the GitLab instance unresponsive to legitimate users by sending multiple concurrent large SAML responses.

Affected

GitLab

CVSS v3.1 GITLAB

7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

0.50% chance of exploitation in the next 30 days, 42nd percentile

Published

2025-09-12

Proof-of-concept exploits (1)

• https://hackerone.com/reports/3019485

Security advisories

• https://about.gitlab.com/releases/2025/09/10/patch-release-gitlab-18-3-2-released

References

• CVE Record
• NVD entry