ALT-PU-2026-17363-3

Package update python3-module-oauthlib in branch c10f2

Version4.0.0-alt1

Published2026-10-07

Max severityMEDIUM

Severity:

Closed issues (4)

MEDIUM6.1

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: 2026-10-13

CVSS 3.xMEDIUM 6.1

CVSS:3.x/CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

References

MEDIUM6.8

OAuthLib is an implementation of the OAuth request-signing logic for Python 3.6+. From 3.0.0 until 4.0.0, OAuthLib's PKCE checks in oauthlib/oauth2/rfc6749/grant_types/authorization_code.py compare attacker-supplied code_verifier values with stored challenges using ordinary string equality in code_challenge_method_plain and code_challenge_method_s256. Because the comparison can return after a length difference or the first mismatching character, repeated token endpoint measurements can reveal common-prefix timing information that could potentially allow recovery of the code_verifier, unauthorized access-token acquisition, and account takeover. Practical exploitation requires an intercepted, single-use authorization code and enough measurements to overcome real-world network noise; the local timing benchmark does not establish practical remote account takeover, so the weakness remains a defense-in-depth concern. This issue is fixed in version 4.0.0.

Published: 2026-10-13Modified: 2026-10-13

CVSS 3.xMEDIUM 6.8

CVSS:3.x/CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

References

GHSA-hj66-6f7g-4r5v

MEDIUM6.1

Oauthlib : Unsafe JSONP callback injection in RevocationEndpoint allows arbitrary JavaScript response generation

Published: 2026-09-29Modified: 2026-10-13

CVSS 3.xMEDIUM 6.1

CVSS:3.x/CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

References

GHSA-xpv3-w29h-x7cv

MEDIUM6.8

Oauthlib: Timing Attack Vulnerability in PKCE code_verifier Comparison (CWE-208)

Published: 2026-09-29Modified: 2026-10-13

CVSS 3.xMEDIUM 6.8

CVSS:3.x/CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

References