{"id":"CVE-2026-77386","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-77386","generatedAt":"2026-10-28T06:00:35.520Z","title":"Prior to 5.1.0, an unauthenticated attacker could initiate the OIDC login flow with an attacker-controlled redirectUrl.","description":"Kyoo is a self-hosted media server focused on movies, series, and anime. Prior to 5.1.0, an unauthenticated attacker could initiate the OIDC login flow with an attacker-controlled redirectUrl. The login handling in auth/oidc.go stored that URL with the opaque login state, and /auth/oidc/logged/{provider} appended the provider, token, and error values before redirecting the victim's browser without validating the destination. Because the one-use token was not bound to the browser session that initiated login, an attacker who induced a victim to complete OIDC authentication could capture the token at the attacker-controlled destination and exchange it through /auth/oidc/callback/{provider} for the victim's Kyoo session. This issue is fixed in version 5.1.0.","published":"2026-09-18T18:17:15.000Z","lastModified":"2026-09-24T21:25:27.000Z","status":"Deferred","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"},"cwe":["CWE-601"],"affected":[],"epss":{"score":0.00559,"percentile":0.46342,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.56%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://github.com/zoriya/Kyoo/commit/02ab3af8127a081295fd7bed103847173c0d7632","source":"security-advisories@github.com"},{"url":"https://github.com/zoriya/Kyoo/pull/1576","source":"security-advisories@github.com"},{"url":"https://github.com/zoriya/Kyoo/releases/tag/v5.1.0","source":"security-advisories@github.com"},{"url":"https://github.com/zoriya/Kyoo/security/advisories/GHSA-xhg6-v78p-xf44","source":"security-advisories@github.com"},{"url":"https://github.com/zoriya/Kyoo/security/advisories/GHSA-xhg6-v78p-xf44","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-77386","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}