@zereight/mcp-gitlab's unauthenticated arbitrary file read via `upload_markdown` enables PAT exfiltration and full account takeover
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 2.1.27
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
The @zereight/mcp-gitlab server, a Model Context Protocol server for GitLab, is affected when its SSE transport mode is enabled, since its tools are exposed without authentication. An unauthenticated remote attacker could use the upload_markdown tool to read arbitrary files on the server, including the server's GitLab access token, and thereby take over the associated GitLab account.
Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.
Read the original 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.
Timeline
- CVE published
- Record last updated
Affected versions
- zereight gitlab-mcp
fixed in 2.1.27
- @zereight/mcp-gitlabnpm
fixed in 2.1.27