{"id":"CVE-2026-48529","sourceIdentifier":"security-advisories@github.com","published":"2026-06-26T17:16:33.820","lastModified":"2026-06-27T04:17:49.630","vulnStatus":"Deferred","cveTags":[],"descriptions":[{"lang":"en","value":"GitHub MCP Server is GitHub's official MCP Server. From 0.22.0 until 1.1.2, when running in HTTP mode with --lockdown-mode enabled, the RepoAccessCache is implemented as a process-global singleton initialized with the first authenticated user's GraphQL client. All subsequent requests from different users share this singleton and their lockdown-related GraphQL queries are executed using the first user's credentials. The singleton is never updated to reflect later users' tokens. This vulnerability is fixed in 1.1.2."}],"affected":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"github","product":"github-mcp-server","versions":[{"version":">= 0.22.0, < 1.1.2","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L","baseScore":6.0,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"LOW","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"LOW"},"exploitabilityScore":1.8,"impactScore":3.7}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-06-27T02:42:44.775898Z","id":"CVE-2026-48529","options":[{"exploitation":"poc"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Secondary","description":[{"lang":"en","value":"CWE-284"}]}],"references":[{"url":"https://github.com/github/github-mcp-server/security/advisories/GHSA-pjp5-fpmr-3349","source":"security-advisories@github.com"},{"url":"https://github.com/github/github-mcp-server/security/advisories/GHSA-pjp5-fpmr-3349","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}]}