{"id":"CVE-2026-79786","title":"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","summary":"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 aut…","severity":"high","cvss":7.1,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N","cwe":["CWE-601"],"published":"2026-08-25","updated":"2026-08-28","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-79786","references":[{"url":"https://github.com/coroot/coroot","label":"disclosure@vulncheck.com"},{"url":"https://github.com/coroot/coroot/blob/v1.24.5/api/mcp_oauth.go","label":"disclosure@vulncheck.com"},{"url":"https://github.com/coroot/coroot/issues/929","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/coroot-1.20.2-through-1.24.5-unvalidated-redirect-uri-in-mcp-oauth-client-registration","label":"disclosure@vulncheck.com"},{"url":"https://github.com/coroot/coroot/issues/929","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"tags":["nvd"],"epss":0.00219,"epssPercentile":0.12671,"ingestedAt":"2026-08-29T21:42:33.765Z","slug":"CVE-2026-79786","body":"## Overview\n\nCoroot'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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":39.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}