| Name | CVE-2026-4786 |
| Description | Mitgation of CVE-2026-4519 was incomplete. If the URL contained "%action" the mitigation could be bypassed for certain browser types the "webbrowser.open()" API could have commands injected into the underlying shell. See CVE-2026-4519 for details. |
| 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) |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| jython (PTS) | bullseye | 2.7.2+repack1-3 | fixed |
| bookworm, trixie | 2.7.3+repack1-1 | fixed |
| forky, sid | 2.7.3+repack1-1 | vulnerable |
| pypy3 (PTS) | bullseye | 7.3.5+dfsg-2+deb11u2 | fixed |
| bullseye (security) | 7.3.5+dfsg-2+deb11u5 | fixed |
| bookworm | 7.3.11+dfsg-2+deb12u3 | fixed |
| trixie | 7.3.19+dfsg-2 | fixed |
| forky, sid | 7.3.21+dfsg-4 | vulnerable |
| python2.7 (PTS) | bullseye | 2.7.18-8+deb11u1 | fixed |
| python3.11 (PTS) | bookworm | 3.11.2-6+deb12u6 | fixed |
| bookworm (security) | 3.11.2-6+deb12u3 | fixed |
| python3.13 (PTS) | trixie | 3.13.5-2 | fixed |
| forky, sid | 3.13.12-1 | vulnerable |
| python3.14 (PTS) | forky | 3.14.3-3 | vulnerable |
| sid | 3.14.4-1 | vulnerable |
| python3.9 (PTS) | bullseye | 3.9.2-1 | vulnerable |
| bullseye (security) | 3.9.2-1+deb11u6 | vulnerable |
The information below is based on the following data on fixed versions.
Notes
[trixie] - python3.13 <not-affected> (Incomplete fix not released)
[bookworm] - python3.11 <not-affected> (Incomplete fix not released)
[bullseye] - python2.7 <not-affected> (Incomplete fix not released)
[trixie] - jython <not-affected> (Incomplete fix not released)
[bookworm] - jython <not-affected> (Incomplete fix not released)
[bullseye] - jython <not-affected> (Incomplete fix not released)
[trixie] - pypy3 <not-affected> (Incomplete fix not released)
[bookworm] - pypy3 <not-affected> (Incomplete fix not released)
[bullseye] - pypy3 <not-affected> (Incomplete fix not released)
Incomplete fix for CVE-2026-4519, followup fixes listed there:
https://mail.python.org/archives/list/security-announce@python.org/thread/JQDUNJVB4AQNTJECSUKOBDU3XCJIPSE5/
https://github.com/python/cpython/issues/148169
https://github.com/python/cpython/pull/148170