| Name | CVE-2026-4519 |
| Description | The webbrowser.open() API would accept leading dashes in the URL which could be handled as command line options for certain web browsers. New behavior rejects leading dashes. Users are recommended to sanitize URLs prior to passing to webbrowser.open(). |
| 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 | vulnerable |
| bookworm, forky, sid, trixie | 2.7.3+repack1-1 | vulnerable |
| 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 | 7.3.21+dfsg-4 | vulnerable |
| sid | 7.3.22+dfsg-1 | fixed |
| python2.7 (PTS) | bullseye | 2.7.18-8+deb11u1 | vulnerable |
| python3.11 (PTS) | bookworm | 3.11.2-6+deb12u6 | vulnerable |
| bookworm (security) | 3.11.2-6+deb12u3 | vulnerable |
| python3.13 (PTS) | trixie | 3.13.5-2 | vulnerable |
| forky, sid | 3.13.12-1 | vulnerable |
| python3.14 (PTS) | forky | 3.14.3-3 | vulnerable |
| sid | 3.14.4-2 | fixed |
| 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.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| jython | source | bullseye | (unfixed) | end-of-life | | |
| jython | source | (unstable) | (unfixed) | | | |
| pypy3 | source | (unstable) | 7.3.22+dfsg-1 | | | |
| python2.7 | source | bullseye | (unfixed) | end-of-life | | |
| python2.7 | source | (unstable) | (unfixed) | | | |
| python3.11 | source | (unstable) | (unfixed) | | | |
| python3.13 | source | (unstable) | (unfixed) | | | |
| python3.14 | source | (unstable) | 3.14.4-1 | | | |
| python3.9 | source | (unstable) | (unfixed) | | | |
Notes
[trixie] - python3.13 <no-dsa> (Minor issue)
[bookworm] - python3.11 <no-dsa> (Minor issue)
[bullseye] - python2.7 <end-of-life> (EOL in bullseye LTS)
[trixie] - jython <no-dsa> (Minor issue)
[bookworm] - jython <no-dsa> (Minor issue)
[bullseye] - jython <end-of-life> (EOL in bullseye LTS)
[trixie] - pypy3 <no-dsa> (Minor issue)
[bookworm] - pypy3 <no-dsa> (Minor issue)
[bullseye] - pypy3 <postponed> (Minor issue)
https://mail.python.org/archives/list/security-announce@python.org/thread/AY5NDSS433JK56Q7Q5IS7B37QFZVVOUS/
https://github.com/python/cpython/issues/143930
https://github.com/python/cpython/pull/143931
Fixed by: https://github.com/python/cpython/commit/82a24a4442312bdcfc4c799885e8b3e00990f02b (main)
Fixed by: https://github.com/python/cpython/commit/9669a912a0e329c094e992204d6bdb8787024d76 (v3.14.4)
Fixed by: https://github.com/python/cpython/commit/43fe06b96f6a6cf5cfd5bdab20b8649374956866 (v3.13.13)
Fixed by: https://github.com/python/cpython/commit/89bfb8e5ed3c7caa241028f1a4eac5f6275a46a4 (v3.13.13)
Fixed by: https://github.com/python/cpython/commit/ceac1efc66516ac387eef2c9a0ce671895b44f03 (3.11 branch)
Fixed by: https://github.com/python/cpython/commit/96fc5048605863c7b6fd6289643feb0e97edd96c (3.11 branch)
Initial fix was incomplete (CVE-2026-4786), to fully address this also needs:
https://github.com/python/cpython/commit/d22922c8a7958353689dc4763dd72da2dea03fff (main)
https://github.com/python/cpython/pull/148516 (3.14)
https://github.com/python/cpython/pull/148517 (3.13)
https://github.com/python/cpython/commit/f4654824ae0850ac87227fb270f9057477946769 (3.11)