High (7.8) in mozilla firefox. EPSS 0.4% chance of exploitation in the next 30 days.
When the Windows DLL "webauthn.dll" was missing from the Operating System, and a malicious one was placed in a folder in the user's %PATH%, Firefox may have loaded the DLL, leading to arbitrary code execution. *Note: This issue only affects the Windows operating system; other operating systems are unaffected.* This vulnerability affects Firefox < 78.
Severity
CVSS 3.1
7.8 high
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
0.4% chance of exploitation in the next 30 days; higher than 35% of CVEs (scores of 2026-10-31)