CVE-2026-16361

Memory safety bugs fixed in Thunderbird ESR 140.13

Critical · published July 21, 2026

CVSS v3.1
9.8
EPSS
0%
Percentile
23.2
In the wild
Unconfirmed
What it is

Memory safety bugs present in Thunderbird ESR 140.12. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox ESR 115.38, Firefox ESR 140.13, and Thunderbird 140.13.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00315 · 23.2th percentile
Published
2026-07-21T12:38Z
EPSS history
Timeline
  • 21 JUL 12:38Z
    Memory safety bugs fixed in Thunderbird ESR 140.13
    cvelistv5