CVE-2026-48529
MEDIUM
MEDIUM
Priority: 0.01
BB Relevance:
52/100
Published: 2026-06-26
Modified: 2026-10-25
First seen: 2026-10-29
Status: active
Attack Surface
Network
No Interaction
Scope Change
CVSS Vector Breakdown
AV:
Network
AC:
High
PR:
Low
UI:
None
S:
Changed
C:
Low
I:
Low
A:
Low
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.