CVE-2026-4721
high
CVSS v3
—
CVSS v4 NEW
—
VIR risk
8.0
Description
RHSA-2026:6917: thunderbird security update (Important)
Predictions
Exploit likelihood
20%
Patch ETA
—
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| rocky | 8 | fixed | |
| rhel | 9 | fixed | |
| debian | sid | fixed | 149.0-1 |
| debian | bookworm | fixed | 140.9.0esr-1~deb12u1 |
| debian | bullseye | fixed | 140.9.0esr-1~deb11u1 |
| debian | forky | fixed | 140.9.0esr-1 |
| debian | trixie | fixed | 140.9.0esr-1~deb13u1 |
| rocky | 9 | fixed | |
| sles | affected | | |
| almalinux | 8 | fixed | firefox-140.9.0-1.el8_10.alma.1.x86_64.rpm |
| almalinux | 9 | fixed | firefox-x11-140.9.0-1.el9_7.alma.1.x86_64.rpm |
| rhel | 8 | fixed | |
References
- https://errata.rockylinux.org/RLSA-2026:5932
- https://access.redhat.com/errata/RHSA-2026:5930
- https://access.redhat.com/errata/RHSA-2026:6188
- https://security-tracker.debian.org/tracker/CVE-2026-4721
- https://errata.rockylinux.org/RLSA-2026:6188
- https://errata.rockylinux.org/RLSA-2026:5930
- https://www.suse.com/security/cve/CVE-2026-4721.html
- https://access.redhat.com/errata/RHSA-2026:5932
- https://bugzilla.redhat.com/2450710
- https://bugzilla.redhat.com/2450711
- https://bugzilla.redhat.com/2450712
- https://bugzilla.redhat.com/2450713
- https://bugzilla.redhat.com/2450714
- https://bugzilla.redhat.com/2450715
- https://bugzilla.redhat.com/2450718
- https://bugzilla.redhat.com/2450719
- https://bugzilla.redhat.com/2450720
- https://bugzilla.redhat.com/2450721
- https://bugzilla.redhat.com/2450722
- https://bugzilla.redhat.com/2450723
- https://bugzilla.redhat.com/2450724
- https://bugzilla.redhat.com/2450725
- https://bugzilla.redhat.com/2450726
- https://bugzilla.redhat.com/2450727
- https://bugzilla.redhat.com/2450728
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.