Back to CVE records
High 7.0Published Apr 13, 2026
CVE-2026-4786Incomplete mitigation of CVE-2026-4519, %action expansion for command injection to webbrowser.open()
Updated under an hour ago ()
Does this affect you?
It affects Python Software Foundation CPython and 13 other products. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Start free and add your stack
Free account, 1 product
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.
- CVSS
- 7.0 HIGH (v4.0, CNA)CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
- Weakness (CWE)
- CWE-77, CWE-88
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- PSF
- NVD analysis
- Awaiting Analysis
- Record last updated
- Aug 12, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Python Software Foundation CPython python_software_foundation:cpython (from the name) | before 3.10.21; from 3.11.0 before 3.11.16; from 3.12.0 before 3.12.14; from 3.13.0 before 3.13.14; from 3.14.0a1 before 3.14.5rc1; from 3.15.0a1 before 3.15.0b1 | CNA record |
Red Hat Red Hat Enterprise Linux 10 redhat:enterprise_linux | from 0:3.12.12-3.el10_1.3 not affected; from 0:3.12.13-2.el10_2 not affected | CISA ADP |
Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support redhat:enterprise_linux_eus | from 0:3.12.9-2.el10_0.9 not affected | CISA ADP |
from 0:2.6.6-70.el6_10.4 not affected | CISA ADP | |
from 0:3.6.8-39.el8_4.11 not affected | CISA ADP | |
Red Hat Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On redhat:rhel_eus_long_life | from 0:3.6.8-39.el8_4.11 not affected | CISA ADP |
from 0:3.6.8-47.el8_6.13 not affected | CISA ADP | |
from 0:3.6.8-47.el8_6.13 not affected | CISA ADP | |
Red Hat Red Hat Enterprise Linux 9.4 Extended Update Support redhat:rhel_eus | from 0:3.11.7-1.el9_4.13 not affected | CISA ADP |
Red Hat RHEL-8 based Middleware Containers redhat:rhosemc | from 7.13.5-4.1777325677 not affected | CISA ADP |
Red Hat Red Hat AI Inference Server 3.2 redhat:ai_inference_server | from 1780681984 not affected | CISA ADP |
Red Hat Red Hat Enterprise Linux AI 3.3 redhat:enterprise_linux_ai | from 1776871984 not affected | CISA ADP |
Red Hat Red Hat Hardened Images redhat:hummingbird | from 3.13.13-1.1.hum1 not affected | CISA ADP |
Red Hat Red Hat Update Infrastructure 5 redhat:rhui | from 1777459441 not affected | CISA ADP |
References
- https://github.com/python/cpython/pull/148170patch
- https://github.com/python/cpython/issues/148169issue-tracking
- https://mail.python.org/archives/list/security-announce@python.org/thread/JQDUNJVB4AQNTJECSUKOBDU3XCJIPSE5/vendor-advisory
- https://github.com/python/cpython/commit/c5767a72838a8dda9d6dc5d3558075b055c56bcapatch
- https://github.com/python/cpython/commit/d22922c8a7958353689dc4763dd72da2dea03fffpatch
- https://github.com/python/cpython/commit/f4654824ae0850ac87227fb270f9057477946769patch
- https://github.com/python/cpython/commit/28b4ad38067bbdad34edfcd03ad2de5f06387e53patch
- https://github.com/python/cpython/commit/d6d68494be70bdbda20f89f83801ba52ec37daa4patch
- https://github.com/python/cpython/commit/a4d3edf3a6ecfde504d02126410d2a65a859b744patch
- https://access.redhat.com/errata/RHSA-2026:10117
- https://access.redhat.com/errata/RHSA-2026:10140
- https://access.redhat.com/errata/RHSA-2026:10141
- https://access.redhat.com/errata/RHSA-2026:10711
- https://access.redhat.com/errata/RHSA-2026:10745
- https://access.redhat.com/errata/RHSA-2026:10774
- https://access.redhat.com/errata/RHSA-2026:10949
- https://access.redhat.com/errata/RHSA-2026:10950
- https://access.redhat.com/errata/RHSA-2026:11062
- https://access.redhat.com/errata/RHSA-2026:11077
- https://access.redhat.com/errata/RHSA-2026:11768
- https://access.redhat.com/errata/RHSA-2026:13692
- https://access.redhat.com/errata/RHSA-2026:13812
- https://access.redhat.com/errata/RHSA-2026:14652
- https://access.redhat.com/errata/RHSA-2026:14653
- https://access.redhat.com/errata/RHSA-2026:14656
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.