CVE-2026-4519
Low
No strong exploitation signal.
CVSS base
3.3
LOW
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
EPSS — probability of exploitation (30 days)
0.3%
23.8th percentile
CISA KEV
Not listed
Weakness / dates
CWE-88
Published 2026-03-20 · modified 2026-08-13
CVSS breakdown
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
| Attack Vector | L | Local |
| Attack Complexity | L | Low |
| Privileges Required | N | None |
| User Interaction | R | Required |
| Scope | U | Unchanged |
| Confidentiality | N | None |
| Integrity | L | Low |
| Availability | N | None |
Timeline
- 2026-03-20 — Published (NVD)
- 2026-08-13 — Last modified (NVD)
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().
Affected
References
- https://github.com/python/cpython/commit/3681d47a440865aead912a054d4599087b4270dd
- https://github.com/python/cpython/commit/43fe06b96f6a6cf5cfd5bdab20b8649374956866
- https://github.com/python/cpython/commit/591ed890270c5697b013bf637029fb3e6cd2d73e
- https://github.com/python/cpython/commit/594b5a05dc9913880ac92eded440defbf32a28d1
- https://github.com/python/cpython/commit/82a24a4442312bdcfc4c799885e8b3e00990f02b
- https://github.com/python/cpython/commit/89bfb8e5ed3c7caa241028f1a4eac5f6275a46a4
- https://github.com/python/cpython/commit/9669a912a0e329c094e992204d6bdb8787024d76
- https://github.com/python/cpython/commit/96fc5048605863c7b6fd6289643feb0e97edd96c
- https://github.com/python/cpython/commit/ad4d5ba32af4d80b0dfa2ba9d8203bfb219e60a5
- https://github.com/python/cpython/commit/cbba6119391112aba9c5aebf7b94aea447922c48
- https://github.com/python/cpython/commit/cc023511238ad93ecc8796157c6f9139a2bb2932
- https://github.com/python/cpython/commit/ceac1efc66516ac387eef2c9a0ce671895b44f03
- https://github.com/python/cpython/issues/143930
- https://github.com/python/cpython/pull/143931
- https://mail.python.org/archives/list/security-announce@python.org/thread/AY5NDSS433JK56Q7Q5IS7B37QFZVVOUS/
- http://www.openwall.com/lists/oss-security/2026/03/20/1
- https://access.redhat.com/errata/RHSA-2026:10065
- https://access.redhat.com/errata/RHSA-2026:10101
- https://access.redhat.com/errata/RHSA-2026:10102
- https://access.redhat.com/errata/RHSA-2026:10111
- https://access.redhat.com/errata/RHSA-2026:10140
- https://access.redhat.com/errata/RHSA-2026:10141
- https://access.redhat.com/errata/RHSA-2026:13812
- https://access.redhat.com/errata/RHSA-2026:16008
- https://access.redhat.com/errata/RHSA-2026:16009
- https://access.redhat.com/errata/RHSA-2026:16030
- https://access.redhat.com/errata/RHSA-2026:16174
- https://access.redhat.com/errata/RHSA-2026:19019
- https://access.redhat.com/errata/RHSA-2026:19064
- https://access.redhat.com/errata/RHSA-2026:19175