CVE-2026-75628
Description
Punk::OAuth2 versions before 0.03 for Perl allow an attacker-chosen off-site redirect after login because same_origin_path accepts a backslash or tab in the return parameter. oauth2_login reads the return parameter from the initiation request, runs same_origin_path over it, and stores the survivor in the session flow record as the post-login redirect target. That check rejects a value that does not begin with a slash, one with a slash as its second byte, and one containing CR or LF. A backslash and a tab pass. The URL Standard treats a backslash as equivalent to a slash for special schemes, so `/\evil.example` parses with the authority `evil.example`. It also strips ASCII tab before parsing, so a tab between two leading slashes leaves `//evil.example`. A crafted link to the application's own login route lands the victim on the attacker's site after a genuine authentication. The redirect carries no authorization code or access token.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
- https://datatracker.ietf.org/doc/html/rfc9700#section-4.11.1
- https://metacpan.org/release/LNATION/Punk-OAuth2-0.02/source/include/pox/pox_util.h#L94
- https://metacpan.org/release/LNATION/Punk-OAuth2-0.03/changes
- https://url.spec.whatwg.org/#concept-basic-url-parser
- https://url.spec.whatwg.org/#relative-slash-state
CWEs
CWE-601
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.