CVE-2026-44895

CRITICAL

GitLab MCP Server: SSE transport has no authentication and wildcard CORS, exposing all GitLab tools

Title source: cna
STIX 2.1

Description

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

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