Story perspectives

New Malware Targets 17 Firefox Add-ons, Users Warned

12/18/2025

Summary

Story summary

Koi Security identified GhostPoster, a malware that infected 17 Firefox add-ons downloaded over 50,000 times.
The malware embeds malicious JavaScript in PNG logo files, enabling affiliate-link hijacking, user monitoring, and disabled security.
The affected extensions including virtual private networks (VPNs) and ad blockers were removed from Firefox Add-ons.
Security experts warn that VPNs often compromise privacy and enable surveillance.
Users should reset passwords and run antivirus software.

1 of 1

Story summary

Koi Security identified GhostPoster, a malware that infected 17 Firefox add-ons downloaded over 50,000 times.
The malware embeds malicious JavaScript in PNG logo files, enabling affiliate-link hijacking, user monitoring, and disabled security.
The affected extensions including virtual private networks (VPNs) and ad blockers were removed from Firefox Add-ons.
Security experts warn that VPNs often compromise privacy and enable surveillance.
Users should reset passwords and run antivirus software.