---
title: "CVE-2026-73649: Velocity.js: Remote Code Execution via property-read to Function constructor (bypass of GHSA-j658-c2gf-x6pq fix)"
url: https://erroneo.us/security/cve/CVE-2026-73649/
description: "CVE-2026-73649 (velocityjs (npm)): Velocity.js is a JavaScript implementation of the Apache Velocity template engine. Prior to 2.1.7, the earlier fix for…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-08-13
date_modified: 2026-08-14
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-73649"
kev: false
cvss: 9.8
epss: 0.00726
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-73649: Velocity.js: Remote Code Execution via property-read to Function constructor (bypass of GHSA-j658-c2gf-x6pq fix)

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.7% , percentile 54: FIRST’s model estimates a 0.7% chance of exploitation activity in the next 30 days, higher than 54% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes velocityjs (npm) <= 2.1.6, fixed in 2.1.7 . Check your lockfile, including transitive dependencies.

## What it is

Velocity.js is a JavaScript implementation of the Apache Velocity template engine. Prior to 2.1.7, the earlier fix for CVE-2026-44966 filtered constructor, proto, and prototype only in the #set assignment handler in src/compile/set.ts, while property-read expressions in src/compile/references.ts remained unfiltered. The getReferences() flow called getAttributes(), whose property access allowed an attacker-controlled template to traverse constructor.constructor to the JavaScript Function constructor. The #set handler validated only the assignment target and did not inspect the right-hand property-read expression, allowing 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.

## Affected packages

- npm `velocityjs` <= 2.1.6 → fixed: 2.1.7

## Affected products (CVE record)

- shepherdwind velocity.js: < 2.1.7

## Severity

- GitHub_M CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.73% probability of exploitation activity in the next 30 days; percentile 54.

## Sources

- [GitHub Advisory GHSA-7gfh-x38p-prh3](https://github.com/advisories/GHSA-7gfh-x38p-prh3)
- [CVE.org record CVE-2026-73649](https://www.cve.org/CVERecord?id=CVE-2026-73649)
- [NVD entry CVE-2026-73649](https://nvd.nist.gov/vuln/detail/CVE-2026-73649)
- [github.com](https://github.com/shepherdwind/velocity.js/security/advisories/GHSA-7gfh-x38p-prh3)
- [github.com](https://github.com/shepherdwind/velocity.js/pull/192)
- [github.com](https://github.com/shepherdwind/velocity.js/commit/f8e47a6c4607249b9c967d3a1ced959b4dd64dba)
- [github.com](https://github.com/shepherdwind/velocity.js/releases/tag/v2.1.7)

---
Source page: https://erroneo.us/security/cve/CVE-2026-73649/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt