CVE-2026-16361

CRITICAL

Memory safety bugs fixed in Firefox ESR 115.38 and Firefox ESR 140.13

Title source: cna
STIX 2.1

Description

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.

Scores

CVSS v3 9.8
EPSS 0.0031
EPSS Percentile 23.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact total

Details

CWE
CWE-119
Status published
Products (5)
mozilla/firefox < 115.38.0
Mozilla/Firefox 115.38 - 115.*
Mozilla/Firefox 140.13
mozilla/thunderbird < 140.13.0
Mozilla/Thunderbird 140.13
Published Jul 21, 2026
Tracked Since Jul 21, 2026