CVE-2025-1020

CRITICAL

Firefox < 135.0 and Thunderbird 131.0-134.0 - Out-of-bounds Write

Title source: llm
STIX 2.1

Description

Memory safety bugs present in Firefox 134 and Thunderbird 134. 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 135 and Thunderbird 135.

References (3)

Core 3

Scores

CVSS v3 9.8
EPSS 0.0059
EPSS Percentile 69.3%
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 no
Technical Impact partial

Details

CWE
CWE-787
Status published
Products (4)
mozilla/firefox < 135.0
Mozilla/Firefox 135
mozilla/thunderbird 131.0 - 135.0
Mozilla/Thunderbird 135
Published Feb 04, 2025
Tracked Since Feb 18, 2026