SSRF in Lfprojects Mcp Registry
CVE-2026-44428
The MCP Registry provides MCP clients with a list of MCP servers, like an app store for MCP servers. Prior to 1.7.6, the client-side and server-side GitHub OIDC flow is bound only to a global audience string, not to the specific registry instance being targeted. On the client side, the publisher always appends audience=mcp-registry when requesting the GitHub Actions ID token, regardless of the selected --registry URL. On the server side, the exchange endpoint validates only that same fixed audience and then derives publish permissions directly from repository_owner. As a result, a token legitimately obtained while interacting with one registry deployment remains acceptable to any other deployment that shares the same code and audience string. This vulnerability is fixed in 1.7.6.
Vulnerability class: SSRF (Server-Side Request Forgery)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (17.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 17th percentile — 17.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Lfprojects Mcp Registry
- Modelcontextprotocol Registry — versions < 1.7.6
Weakness classification (CWE)
References
- github.com/modelcontextprotocol/registry/security/advisories/GHSA-95c3-6vvw-4mrq (Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-44428?
- CVE-2026-44428 is a medium-severity vulnerability in Lfprojects Mcp Registry, classified under Server-Side Request Forgery (SSRF). CVSS score: 4.7/10. Published 2026-05-14.
- How severe is CVE-2026-44428?
- Medium severity. CVSS v3 base score is 4.7 out of 10.