{"id":"CVE-2026-79786","aliases":["EUVD-2026-65698","GHSA-g3gf-mwj7-2hc4"],"status":"published","title":"Coroot 1.20.2 through 1.24.5 Unvalidated Redirect URI in MCP OAuth Client Registration","description":"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.","severity":{"version":"4.0","score":7,"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","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00388,"percentile":0.3328,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-601"],"published":"2026-08-25T18:23:14Z","modified":"2026-10-28T02:31:00Z","products":[{"vendor":"coroot","product":"coroot"}],"references":[{"url":"https://github.com/coroot/coroot","tags":["product","package"]},{"url":"https://github.com/coroot/coroot/issues/929","tags":["issue-tracking","exploit","report"]},{"url":"https://github.com/coroot/coroot/blob/v1.24.5/api/mcp_oauth.go","tags":["technical-description","article"]},{"url":"https://www.vulncheck.com/advisories/coroot-1.20.2-through-1.24.5-unvalidated-redirect-uri-in-mcp-oauth-client-registration","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-79786","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-g3gf-mwj7-2hc4"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/79xxx/CVE-2026-79786.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-79786","title":"Coroot 1.20.2 through 1.24.5 Unvalidated Redirect URI in MCP OAuth Client Registration","description":"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.","status":"published","published":"2026-08-25T18:23:14.494Z","modified":"2026-08-28T22:33:16.534Z","cvss":[{"version":"4.0","score":7,"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","level":"high","assessor":"cna"},{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-601"],"updated_at":"2026-11-02T13:50:38.739766Z"}],"euvd":[{"id":"EUVD-2026-65698","description":"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.","status":"published","published":"2026-08-25T18:23:14Z","modified":"2026-08-28T22:33:16Z","cvss":[{"version":"4.0","score":7,"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","level":"high"}],"updated_at":"2026-11-02T18:01:22.342607Z"}],"ghsa":[{"id":"GHSA-g3gf-mwj7-2hc4","title":"Coroot's unauthenticated MCP OAuth dynamic client registration endpoint accepts any syntactically...","description":"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.","status":"published","published":"2026-08-25T21:31:29Z","modified":"2026-08-25T21:31:34Z","cvss":[{"version":"4.0","score":7,"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","level":"high"},{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N","level":"high"}],"cwes":["CWE-601"],"updated_at":"2026-11-02T15:10:58.645101Z"}],"nvd":[{"id":"CVE-2026-79786","description":"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.","status":"published","published":"2026-08-25T19:16:54.75Z","modified":"2026-09-23T17:17:43.03Z","cvss":[{"version":"4.0","score":7,"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","level":"high","assessor":"secondary"},{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N","level":"high","assessor":"secondary"}],"cwes":["CWE-601"],"updated_at":"2026-11-02T14:12:41.347728Z"}],"osv":[{"id":"CVE-2026-79786","title":"Coroot 1.20.2 through 1.24.5 Unvalidated Redirect URI in MCP OAuth Client Registration","description":"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.","status":"published","published":"2026-08-25T18:23:14.494Z","modified":"2026-10-28T02:31:00.74676163Z","cvss":[{"version":"4.0","score":7,"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","level":"high"}],"cwes":["CWE-601"],"updated_at":"2026-11-02T15:45:17.44708Z"}]}}