| Name | CVE-2026-15806 |
| Description | The HTTPPasswordMgr class in the urllib.request module, along with its subclasses HTTPPasswordMgrWithDefaultRealm and HTTPPasswordMgrWithPriorAuth, did not take the URL scheme into account when matching stored credentials against a requested URL. Credentials added for an https:// URL were also used for requests to the same host over http://, so an attacker able to redirect or downgrade a client to plain HTTP (for example, via an HTTPS-to-HTTP redirect or an on-path position) could capture credentials in cleartext. Credentials added for http:// URLs could likewise be sent over https://. Credential matching is now scoped by URL scheme. Credentials registered with a URL that includes a scheme are only used for requests with the same scheme. Credentials registered with a bare authority (such as example.com or example.com:8080) continue to match any scheme, preserving compatibility with existing code, including proxy authentication. Users who cannot upgrade immediately can mitigate by ensuring that applications never make plain http:// requests to hosts for which credentials are registered, for example by not following redirects to http:// URLs. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| pypy3 (PTS) | bullseye | 7.3.5+dfsg-2+deb11u2 | vulnerable |
| bullseye (security) | 7.3.5+dfsg-2+deb11u5 | vulnerable | |
| bookworm | 7.3.11+dfsg-2+deb12u3 | vulnerable | |
| trixie | 7.3.19+dfsg-2 | vulnerable | |
| forky, sid | 7.3.23+dfsg-1 | vulnerable | |
| python2.7 (PTS) | bullseye | 2.7.18-8+deb11u1 | vulnerable |
| python3.11 (PTS) | bookworm | 3.11.2-6+deb12u8 | vulnerable |
| bookworm (security) | 3.11.2-6+deb12u3 | vulnerable | |
| python3.13 (PTS) | trixie | 3.13.5-2+deb13u3 | vulnerable |
| forky | 3.13.14-1 | vulnerable | |
| sid | 3.13.15-1 | vulnerable | |
| python3.14 (PTS) | forky | 3.14.6-1 | vulnerable |
| sid | 3.14.7-1 | vulnerable | |
| python3.15 (PTS) | forky, sid | 3.15.0~rc1-1 | vulnerable |
| python3.9 (PTS) | bullseye | 3.9.2-1 | vulnerable |
| bullseye (security) | 3.9.2-1+deb11u7 | vulnerable |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| pypy3 | source | (unstable) | (unfixed) | |||
| python2.7 | source | (unstable) | (unfixed) | |||
| python3.11 | source | (unstable) | (unfixed) | |||
| python3.13 | source | (unstable) | (unfixed) | |||
| python3.14 | source | (unstable) | (unfixed) | |||
| python3.15 | source | (unstable) | (unfixed) | |||
| python3.9 | source | (unstable) | (unfixed) |
https://mail.python.org/archives/list/security-announce@python.org/thread/3OKPE5S75KDNA7FY7AI3PL2MXM2X5RB3/
https://github.com/python/cpython/issues/155694
https://github.com/python/cpython/pull/155696
Fixed by: https://github.com/python/cpython/commit/a7bb524fef61f77ede01f660ffbd591e1d5837ce (main)
Fixed by: https://github.com/python/cpython/commit/641be42bb07921ba0f8bffe228b1dc706b092ef6 (3.15 branch)
Fixed by: https://github.com/python/cpython/commit/a0d023fbd23773e24b35d8368789470e22cda5d8 (3.14 branch)
Fixed by: https://github.com/python/cpython/commit/a2773a34183b7d94a243bb98fd658926cc5348ce (3.13 branch)