CVE-2021-28918
CRITICAL9.1EPSS 85.9%Improper parsing of octal bytes in netmask
Published: 4/14/2021Modified: 3/13/2026
Also known as:GHSA-4c7m-wxvm-r7gc
Description
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. :exclamation: NOTE: The fix for this issue was incomplete. A subsequent fix was made in version `2.0.1` which was assigned [CVE-2021-29418 / GHSA-pch5-whg9-qr2r](https://github.com/advisories/GHSA-pch5-whg9-qr2r). For complete protection from this vulnerability an upgrade to version 2.0.1 or later is recommended.
Affected packages (1)
- npm/netmaskfrom 0, < 1.1.0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | CRITICAL9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
References (9)
- ADVISORYhttps://github.com/advisories/GHSA-pch5-whg9-qr2r
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2021-28918
- WEBhttps://github.com/rs/node-netmask
- WEBhttps://github.com/rs/node-netmask/blob/98294cb20695f2c6c36219a4fbcd4744fb8d0682/CHANGELOG.md#v110-mar-18-2021
- WEBhttps://github.com/sickcodes/security/blob/master/advisories/SICK-2021-011.md
- WEBhttps://rootdaemon.com/2021/03/29/vulnerability-in-netmask-npm-package-affects-280000-projects
- WEBhttps://security.netapp.com/advisory/ntap-20210528-0010
- WEBhttps://www.bleepingcomputer.com/news/security/critical-netmask-networking-bug-impacts-thousands-of-applications
- WEBhttps://www.npmjs.com/package/netmask