CVE-2026-79786

Coroot's unauthenticated MCP OAuth dynamic client registration endpoint accepts any syntactically valid redirect URI without validation, allowing attackers to register clients pointing to attacker-controlled hosts. Attackers can send authorization URLs to signed-in users, capture their authorization codes upon consent approval, and exchange them for access tokens to hijack MCP sessions.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/coroot/coroot
https://github.com/coroot/coroot/blob/v1.24.5/api/mcp_oauth.go
https://github.com/coroot/coroot/issues/929
https://www.vulncheck.com/advisories/coroot-1.20.2-through-1.24.5-unvalidated-redirect-uri-in-mcp-oauth-client-registration
https://github.com/coroot/coroot/issues/929

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-25 19:16

Updated : 2026-08-28 23:17

NVD link : CVE-2026-79786

Mitre link : CVE-2026-79786

CVE.ORG link : CVE-2026-79786

JSON object : View

Products Affected

No product.

CWE

CWE-601

URL Redirection to Untrusted Site ('Open Redirect')

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