{"id":"CVE-2026-44428","sourceIdentifier":"security-advisories@github.com","published":"2026-05-14T22:16:44.593","lastModified":"2026-10-26T14:10:00.130","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"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."},{"lang":"es","value":"El Registro MCP proporciona a los clientes MCP una lista de servidores MCP, como una tienda de aplicaciones para servidores MCP. Antes de la versión 1.7.6, el flujo OIDC de GitHub del lado del cliente y del lado del servidor está vinculado únicamente a una cadena de audiencia global, no a la instancia de registro específica a la que se apunta. Del lado del cliente, el publicador siempre añade audience=mcp-registry al solicitar el token de ID de GitHub Actions, independientemente de la URL --registry seleccionada. Del lado del servidor, el punto final de intercambio valida únicamente esa misma audiencia fija y luego deriva los permisos de publicación directamente de repository_owner. Como resultado, un token obtenido legítimamente mientras se interactúa con una implementación de registro sigue siendo aceptable para cualquier otra implementación que comparta el mismo código y cadena de audiencia. Esta vulnerabilidad está corregida en la versión 1.7.6."}],"affected":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"modelcontextprotocol","product":"registry","versions":[{"version":"< 1.7.6","status":"affected"}]}]}],"metrics":{"cvssMetricV40":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:L/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","baseScore":2.1,"baseSeverity":"LOW","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"ACTIVE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"LOW","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}}],"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N","baseScore":4.7,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"REQUIRED","scope":"CHANGED","confidentialityImpact":"NONE","integrityImpact":"LOW","availabilityImpact":"NONE"},"exploitabilityScore":2.8,"impactScore":1.4}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-05-15T14:22:02.074993Z","id":"CVE-2026-44428","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Secondary","description":[{"lang":"en","value":"CWE-918"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:lfprojects:mcp_registry:*:*:*:*:*:*:*:*","versionEndExcluding":"1.7.6","matchCriteriaId":"E1BC5309-2424-4E6E-B821-B3172A46BC05"}]}]}],"references":[{"url":"https://github.com/modelcontextprotocol/registry/security/advisories/GHSA-95c3-6vvw-4mrq","source":"security-advisories@github.com","tags":["Mitigation","Vendor Advisory"]}]}