CVE-2026-44966
Velocity.js: Prototype Pollution in #set path assignment
Description
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.
INFO
Published Date :
May 26, 2026, 10:16 p.m.
Last Modified :
July 24, 2026, 12:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | MITRE-CVE | ||||
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update Velocity.js to version 2.1.6 or later.
- Avoid rendering user-controlled templates.
- Sanitize all template inputs.
- Implement strict input validation.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-44966.
| URL | Resource |
|---|---|
| https://github.com/shepherdwind/velocity.js/security/advisories/GHSA-j658-c2gf-x6pq | Exploit Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-44966 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-44966
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-44966 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-44966 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Translated by [email protected]
Jul. 24, 2026
Action Type Old Value New Value Changed Translation Title: Velocity.js de shepherdwind, Description: Velocity.js es una implementación JavaScript del motor de plantillas Apache Velocity. En 2.1.5 y versiones anteriores, se descubrió una vulnerabilidad de contaminación de prototipos en velocityjs. Este problema ocurre durante el procesamiento de las directivas #set en las plantillas Velocity. Si una aplicación renderiza una plantilla controlada por un atacante, es posible modificar Object.prototype, lo que podría llevar a una denegación de servicio (DoS) o a una ejecución remota de código (RCE) dependiendo del entorno del servidor. Title: Velocity.js de shepherdwind, Description: Velocity.js es una implementación JavaScript del motor de plantillas Apache Velocity. En 2.1.5 y versiones anteriores, se descubrió una vulnerabilidad de contaminación de prototipos en velocityjs. Este problema ocurre durante el procesamiento de las directivas #set en las plantillas Velocity. Si una aplicación renderiza una plantilla controlada por un atacante, es posible modificar Object.prototype, lo que podría llevar a una denegación de servicio (DoS) o a una ejecución remota de código (RCE) dependiendo del entorno del servidor. -
CVE Translated by [email protected]
Jul. 23, 2026
Action Type Old Value New Value Added Translation Title: Velocity.js de shepherdwind, Description: Velocity.js es una implementación JavaScript del motor de plantillas Apache Velocity. En 2.1.5 y versiones anteriores, se descubrió una vulnerabilidad de contaminación de prototipos en velocityjs. Este problema ocurre durante el procesamiento de las directivas #set en las plantillas Velocity. Si una aplicación renderiza una plantilla controlada por un atacante, es posible modificar Object.prototype, lo que podría llevar a una denegación de servicio (DoS) o a una ejecución remota de código (RCE) dependiendo del entorno del servidor. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'shepherdwind', 'product': 'velocity.js', 'versions': [{'status': 'affected', 'version': '<= 2.1.5'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-44966', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-01T17:04:32.448870Z'} -
Initial Analysis by [email protected]
Jun. 02, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Added CPE Configuration OR *cpe:2.3:a:shepherdwind:velocity.js:*:*:*:*:*:node.js:*:* versions up to (including) 2.1.5 Added Reference Type GitHub, Inc.: https://github.com/shepherdwind/velocity.js/security/advisories/GHSA-j658-c2gf-x6pq Types: Exploit, Vendor Advisory -
New CVE Received by [email protected]
May. 26, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L Added CWE CWE-1321 Added Reference https://github.com/shepherdwind/velocity.js/security/advisories/GHSA-j658-c2gf-x6pq