CVE-2021-28918: Netmask Project Netmask

Critical severity, CVSS 9.1. EPSS: 16.7% chance of exploitation in the next 30 days.

Improper input validation of octal strings in netmask npm package v1.0.6 and below allows unauthenticated remote attackers to perform indeterminate SSRF, RFI, and LFI attacks on many of the dependent packages. A remote unauthenticated attacker can bypass packages relying on netmask to filter IPs and reach critical VPN or LAN hosts.

Affected products

• Netmask Project Netmask: up to and including 1.0.6

Published 2021-04-01. Last modified 2026-06-17.