Vulnerability · Published Sep 15, 2026 · Assigned by GitHub_M
CVE-2026-61560@zereight/mcp-gitlab's unauthenticated arbitrary file read via `upload_markdown` enables PAT exfiltration and full account takeover
Critical 9.8
In plain English
A critical-severity path traversal in gitlab-mcp from zereight. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 2.9% (higher than 87% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei. Fixed versions are available - upgrade the affected package.
Official description
`@zereight/mcp-gitlab` is a Model Context Protocol server for GitLab. Prior to version 2.1.27, the SSE transport mode (`SSE=true`) exposes all MCP tools without any authentication. The `upload_markdown` tool reads arbitrary files from the server's local filesystem via an unsanitized `file_path` parameter and uploads them to a GitLab project. Combined, any unauthenticated network-reachable attacker can read `/proc/self/environ` to steal the server's `GITLAB_PERSONAL_ACCESS_TOKEN` and achieve full GitLab account takeover. This is the default configuration for Docker deployments. Version 2.1.27 contains a patch.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | @zereight/mcp-gitlab | 2.1.27 | GHSA-cv3r-c5h8-f4g5 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| zereight | gitlab-mcp | < 2.1.27 |
Weakness: CWE-22 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
- https://github.com/zereight/gitlab-mcp/security/advisories/GHSA-cv3r-c5h8-f4g5 x_refsource_CONFIRM
- https://github.com/zereight/gitlab-mcp/pull/482 x_refsource_MISC
- https://github.com/zereight/gitlab-mcp/pull/554 x_refsource_MISC
- https://github.com/zereight/gitlab-mcp/pull/622 x_refsource_MISC