Bug 2567523 (CVE-2026-123271) - CVE-2026-123271 github.com/diillson/chatcli: ChatCLI: Unauthorized access via unvalidated MCP OAuth resource indicator
Summary: CVE-2026-123271 github.com/diillson/chatcli: ChatCLI: Unauthorized access via...
Keywords:
Status: NEW
Alias: CVE-2026-123271
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security DevOps Team
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Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-11-05 22:04 UTC by OSIDB Bzimport
Modified: 2026-11-05 22:54 UTC (History)
0 users

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Description OSIDB Bzimport 2026-11-05 22:04:40 UTC 
ChatCLI before v1.215.2 contains an improper validation vulnerability in the MCP OAuth login flow that uses server-supplied Protected Resource Metadata as the resource indicator without checking it matches the configured server URL. A malicious MCP server can declare another resource on the same authorization server, obtain the user's bearer token for it, and replay that token against the other resource.
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