CVE-2026-48529

medium

Description

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.

References

https://github.com/github/github-mcp-server/security/advisories/GHSA-pjp5-fpmr-3349

Details

Source: Mitre, NVD

Published: 2026-06-26

Updated: 2026-06-27

Risk Information

CVSS v2

Base Score: 4.6

Vector: CVSS2#AV:N/AC:H/Au:S/C:P/I:P/A:P

Severity: Medium

CVSS v3

Base Score: 6

Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L