CVE-2024-45489: The Browser Company Arc

Critical severity, CVSS 9.8. EPSS: 1.2% chance of exploitation in the next 30 days.

Arc before 2024-08-26 allows remote code execution in JavaScript boosts. Boosts that run JavaScript cannot be shared by default; however (because of misconfigured Firebase ACLs), it is possible to create or update a boost using another user's ID. This installs the boost in the victim's browser and runs arbitrary Javascript on that browser in a privileged context. NOTE: this is a no-action cloud vulnerability with zero affected users.

Affected products

Published 2024-09-20. Last modified 2026-06-17.