CVE-2026-5735

CRITICAL

Memory safety bugs fixed in Firefox 149.0.2 and Thunderbird 149.0.2

Title source: cna
STIX 2.1

Description

Memory safety bugs present in Firefox 149.0.1 and Thunderbird 149.0.1. 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 149.0.2 and Thunderbird 149.0.2.

References (3)

Core 3

Scores

CVSS v3 9.8
EPSS 0.0031
EPSS Percentile 22.1%
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 no
Technical Impact total

Details

CWE
CWE-125 CWE-787
Status published
Products (6)
mozilla/firefox < 149.0.2
Mozilla/Firefox 149.0.2
Mozilla/Firefox unspecified - 149.0.2
mozilla/thunderbird < 149.0.2
Mozilla/Thunderbird 149.0.2
Mozilla/Thunderbird unspecified - 149.0.2
Published Apr 07, 2026
Tracked Since Apr 07, 2026