CVE-2026-109705EPSS p22.5%

CVE-2026-109705CVE-2026-109705

Description

Sandbox escape, site isolation issue due to incorrect boundary conditions, use-after-free in the Networking component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.

Scoring

CVSS 9.6 ()
VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
EPSS0.31% probability of exploitation · percentile 22.5% · 2026-10-17T12:00:28Z
Last modified2026-10-13
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.