CVE-2026-49264: medium-severity vulnerability in oauthlib
OAuthLib: Unsafe JSONP callback injection in RevocationEndpoint allows arbitrary JavaScript response generation
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.1epss 0.2%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Affected products
oauthlib · oauthlibRelated CVEs — oauthlib
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