{"id":"CVE-2026-49264","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-49264","generatedAt":"2026-10-28T01:50:38.423Z","title":"A browser application that loads the revocation response as trusted JSONP and permits attacker influence over callback can therefore execute attacker-controlled JavaScript in the including application's origin, with access to its DOM and…","description":"OAuthLib is an implementation of the OAuth request-signing logic for Python 3.6+. From 0.6.1 until 4.0.0, OAuthLib's RevocationEndpoint in oauthlib/oauth2/rfc6749/endpoints/revocation.py reflects an unvalidated callback request parameter into success and error response bodies when enable_jsonp=True. The callback can come from the query string or request body and is used without restricting it to a legal JavaScript function name. A browser application that loads the revocation response as trusted JSONP and permits attacker influence over callback can therefore execute attacker-controlled JavaScript in the including application's origin, with access to its DOM and script-accessible data. The feature is disabled by default, so only deployments that explicitly enable JSONP are affected. This issue is fixed in version 4.0.0.","published":"2026-10-13T16:17:21.000Z","lastModified":"2026-10-16T23:17:02.000Z","status":"Deferred","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":6.1,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"},"cwe":["CWE-79"],"affected":[],"epss":{"score":0.00234,"percentile":0.14229,"date":"2026-10-26","history":[{"date":"2026-10-14","score":0.00314,"percentile":0.22621}]},"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 (0.23%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-13T16:17:21.000Z","detail":{"score":"6.1","severity":"MEDIUM","publishedAt":"2026-10-13T16:17:20.560Z"},"summary":"New CVE, medium severity (CVSS 6.1)."}],"references":[{"url":"https://github.com/oauthlib/oauthlib/commit/c888359f3c42bec235b2c5caab2069c9ed62457c","source":"security-advisories@github.com"},{"url":"https://github.com/oauthlib/oauthlib/pull/951","source":"security-advisories@github.com"},{"url":"https://github.com/oauthlib/oauthlib/releases/tag/v4.0.0","source":"security-advisories@github.com"},{"url":"https://github.com/oauthlib/oauthlib/security/advisories/GHSA-hj66-6f7g-4r5v","source":"security-advisories@github.com"},{"url":"https://github.com/oauthlib/oauthlib/security/advisories/GHSA-hj66-6f7g-4r5v","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-49264","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."}