What is CVE-2021-44908?

CVE-2021-44908 is a critical-severity vulnerability in Sailsjs Sails, classified under Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). CVSS score: 9.8/10. Published 2022-03-17.

How severe is CVE-2021-44908?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Prototype Pollution in Sailsjs Sails

CVE-2021-44908

SailsJS Sails.js <=1.4.0 is vulnerable to Prototype Pollution via controller/load-action-modules.js, function loadActionModules().

Vulnerability class: Prototype Pollution

Published 2022-03-17 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.018 (78.0th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 78th percentile — 78.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.018 · newest: 0.018 · change: 0.000

Affected products

Sailsjs Sails

Weakness classification (CWE)

CWE-1321 — Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution)

References

github.com/Marynk/JavaScript-vulnerability-detection/blob/main/sailsJS PoC.zip (Broken Link)
github.com/balderdashy/sails/blob/master/lib/app/private/controller/load-action… (Third Party Advisory)
github.com/balderdashy/sails/issues/7209 (Exploit, Patch, Third Party Advisory, Issue Tracking)

Frequently asked questions

What is CVE-2021-44908?: CVE-2021-44908 is a critical-severity vulnerability in Sailsjs Sails, classified under Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). CVSS score: 9.8/10. Published 2022-03-17.
How severe is CVE-2021-44908?: Critical severity. CVSS v3 base score is 9.8 out of 10.