CVE-2026-79786

7.0 HIGH 0.4% exploit odds No fix listed Other

What it is

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.

At a glance

Exploitability: Can be exploited over the network without logging in, but needs a user to act. High risk of data exposure.
Exploit odds: 0.4% chance of exploitation in the next 30 days (EPSS).
Fix: No patch or advisory is linked yet. Look at mitigations or restrict exposure.

Timeline

2026-08-25 19:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-09-23 17:17 UTC Last updatedMost recent change to the record

Details

Published: 2026-08-25 19:16 UTC
Last modified: 2026-09-23 17:17 UTC
Exploit probability: 0.4% · EPSS, next 30 days
Weakness: CWE-601
Record status: Deferred

Attack profile CVSS 4.0 · 7.0

Attack vector: Network
Complexity: Low
Attack requirements: None
Privileges needed: None
User interaction: Active
Confidentiality: High
Integrity: Low
Availability: None

Raw vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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References

NVD record · CVE.org record