CVE-2026-4519

NameCVE-2026-4519
DescriptionThe 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().
SourceCVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
ReferencesDLA-4583-1
Debian Bugs1136197

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
jython (PTS)bullseye2.7.2+repack1-3vulnerable
forky, sid, bookworm, trixie2.7.3+repack1-1vulnerable
pypy3 (PTS)bullseye7.3.5+dfsg-2+deb11u2vulnerable
bullseye (security)7.3.5+dfsg-2+deb11u5vulnerable
bookworm7.3.11+dfsg-2+deb12u3vulnerable
trixie7.3.19+dfsg-2vulnerable
forky, sid7.3.22+dfsg-1fixed
python2.7 (PTS)bullseye2.7.18-8+deb11u1vulnerable
python3.11 (PTS)bookworm3.11.2-6+deb12u7vulnerable
bookworm (security)3.11.2-6+deb12u3vulnerable
python3.13 (PTS)trixie3.13.5-2+deb13u2fixed
forky, sid3.13.12-1vulnerable
python3.14 (PTS)forky3.14.4-2fixed
sid3.14.5-1fixed
python3.9 (PTS)bullseye3.9.2-1vulnerable
bullseye (security)3.9.2-1+deb11u7fixed

The information below is based on the following data on fixed versions.

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs
jythonsourcebullseye(unfixed)end-of-life
jythonsource(unstable)(unfixed)1136197
pypy3source(unstable)7.3.22+dfsg-1
python2.7sourcebullseye(unfixed)end-of-life
python2.7source(unstable)(unfixed)
python3.11source(unstable)(unfixed)
python3.13sourcetrixie3.13.5-2+deb13u2
python3.13source(unstable)(unfixed)
python3.14source(unstable)3.14.4-1
python3.9sourcebullseye3.9.2-1+deb11u7DLA-4583-1
python3.9source(unstable)(unfixed)

Notes

[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/commit/28b4ad38067bbdad34edfcd03ad2de5f06387e53 (v3.14.5rc1)
https://github.com/python/cpython/pull/148517 (3.13)
https://github.com/python/cpython/commit/d6d68494be70bdbda20f89f83801ba52ec37daa4 (3.13)
https://github.com/python/cpython/commit/f4654824ae0850ac87227fb270f9057477946769 (3.11)

Search for package or bug name: Reporting problems