A potentially exploitable use-after-free crash during actor destruction with service workers. This issue does not affect releases earlier than Firefox 49. This vulnerability affects Firefox < 49.0.2.
Severity
CVSS 3.0
9.8 critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
2.3% chance of exploitation in the next 30 days; higher than 83% of CVEs (scores of 2026-10-31)