CVE-2026-44966

HighCVSS 8.3

Published: 26/05/2026(UTC)Updated: 24/07/2026(UTC)Translated: 24/07/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.51%

40th percentile - higher than 40% of all known CVEs

Summary

Velocity.js is a JavaScript implementation of the Apache Velocity template engine. In 2.1.5 and earlier, a prototype pollution vulnerability was discovered. This issue occurs during the processing of #set directives in Velocity templates. If an application renders a template controlled by an attacker, it is possible to modify Object.prototype, potentially leading to Denial of Service (DoS) or Remote Code Execution (RCE) depending on the server environment.

Risk Assessment

An attacker can cause application crashes or take control, threatening the availability and security of systems using Velocity.js.

Recommendation

Update Velocity.js to version 2.1.6 or later. Avoid rendering templates from untrusted sources.

Other vulnerabilities in Velocity.js

CVE-2026-73649Critical
Velocity.js before 2.1.7 does not filter property-read expressions in src/compile/references.ts, allowing access to the Function constructor via constructor.constructor. Although the #set handler validates the assignment target, it does not inspect the right-hand property-read expression, enabling arbitrary shell commands, environment-variable access, cloud-credential access, and internal-network access in the server process. This issue is fixed in version 2.1.7.

Original NVD description (English source)

Velocity.js is a JavaScript implementation of the Apache Velocity template engine. In 2.1.5 and earlier, a prototype pollution vulnerability was discovered in velocityjs. This issue occurs during the processing of #set directives in Velocity templates. If an application renders a template controlled by an attacker, it is possible to modify Object.prototype, potentially leading to Denial of Service (DoS) or Remote Code Execution (RCE) depending on the server environment.