CVE Almanac
← All CVEs

CVE-2026-12329

MEDIUM 5.3

Published 2026-06-16 · Last modified 2026-06-30

Memory safety bug fixed in Thunderbird ESR 140.12. This vulnerability was fixed in Firefox ESR 140.12 and Thunderbird 140.12.

NO EXPLOITATION SIGNALS

No known exploitation, public exploit, or elevated probability at this time. Track for changes.

Exploitation likelihood

0.3%chance of exploitation in 30 days · 23rd percentile

○ In CISA KEV ○ Public exploit / PoC

Impact if exploited

5.3CVSS 3.1 · MEDIUM

  • ConfidentialityNone
  • IntegrityNone
  • AvailabilityLow

What an attacker needs

  • ✓Access: Reachable over the network — no local access needed
  • ✓Privileges: No account or privileges required
  • ✓User interaction: No user interaction needed
  • ✓Complexity: No special conditions — reliably repeatable

✓ lowers the bar for an attacker · ⚠ raises it

Affected

Vendors Mozilla Red Hat

Products Firefox Thunderbird Red Hat Enterprise Linux Appstream (V. 10) Red Hat Enterprise Linux Appstream (V. 8) Red Hat Enterprise Linux Appstream (V. 9) Red Hat Enterprise Linux 10 Red Hat Enterprise Linux 6 Red Hat Enterprise Linux 7

Weakness (CWE)

  • CWE-119: Memory buffer overflow
  • CWE-416: Use after free
  • CWE-476: NULL pointer dereference

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References

Advisories

Technical & other

Sources: NVD · CVE.org · EPSS