CVE-2026-44895
CRITICALGitLab MCP Server: SSE transport has no authentication and wildcard CORS, exposing all GitLab tools
Title source: cnaDescription
GitLab MCP Server lets an AI agent talk directly to GitLab. Prior to 0.6.0, the HTTP transport in src/transport.ts ships with no authentication layer at all and a wildcard Access-Control-Allow-Origin: * on every response. The structural defect is that the SSE server stands up a stateful, mutation-capable RPC endpoint that is backed by the operator's GITLAB_PERSONAL_ACCESS_TOKEN without any inbound credential check, then advertises itself to every cross-origin browser context via the wildcard CORS header. The httpServer.listen(port) call at line 97 also passes no host argument, so the bind defaults to 0.0.0.0 and exposes the auth-less surface on every interface. This vulnerability is fixed in 0.6.0.
References (1)
Core 1
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/yoda-digital/mcp-gitlab-server/security/advisories/GHSA-8jr5-6gvj-rfpf
Scores
CVSS v4
9.2
EPSS
0.0039
EPSS Percentile
30.8%
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
yes
Technical Impact
total
Details
CWE
CWE-306
CWE-942
Status
published
Products (2)
yoda-digital/mcp-gitlab-server
< 0.6.0
yoda.digital/gitlab-mcp-server
0 - 0.6.0npm
Published
May 26, 2026
Tracked Since
May 27, 2026