CVE-2026-0878

HIGH

Firefox < 147.0 and 140.7-140.* - Sandbox Escape via CanvasWebGL Boundary Condition Mismanagement

Title source: llm
STIX 2.1

Description

Sandbox escape due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 147, Firefox ESR 140.7, Thunderbird 147, and Thunderbird 140.7.

References (31)

Core 31
Core References

Scores

CVSS v3 8.0
EPSS 0.0042
EPSS Percentile 33.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-119 CWE-20
Status published
Products (8)
mozilla/firefox < 140.7.0
mozilla/firefox < 147.0
Mozilla/Firefox 140.7 - 140.*
Mozilla/Firefox 147
mozilla/thunderbird < 140.7.0
mozilla/thunderbird < 147.0
Mozilla/Thunderbird 140.7 - 140.*
Mozilla/Thunderbird 147
Published Jan 13, 2026
Tracked Since Feb 18, 2026