CVE-2023-0921 — A lack of length validation in GitLab CE/EE affecting all versions from 8

A lack of length validation in GitLab CE/EE affecting all versions from 8.3 before 15.10.8, 15.11 before 15.11.7, and 16.0 before 16.0.2 allows an authenticated attacker to create a large Issue description via GraphQL which, when repeatedly requested, saturates CPU usage.

01What is this vulnerability?

A lack of length validation in GitLab CE/EE affecting all versions from 8.3 before 15.10.8, 15.11 before 15.11.7, and 16.0 before 16.0.2 allows an authenticated attacker to create a large Issue description via GraphQL which, when repeatedly requested, saturates CPU usage.

02Affected products

Vendor	Product	Versions
GitLab	GitLab	>=8.3, <15.10.8, >=15.11, <15.11.7, >=16.0, <16.0.2

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2023-06-06T00:00:00.000Z
• Last modified: 2025-01-07T21:51:37.372Z

09References

• gitlab.com — https://gitlab.com/gitlab-org/gitlab/-/issues/392433
• hackerone.com — https://hackerone.com/reports/1869839
• gitlab.com — https://gitlab.com/gitlab-org/cves/-/blob/master/2023/CVE-2023-0921.json