CVE-2019-19919

CRITICAL

handlebars.js - Prototype Pollution leading to Remote Code Execution

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2019-19919. PoCs published by fazilbaig1.

AI-analyzed exploit summary This repository contains a functional exploit and scanner for CVE-2019-19919, a Handlebars template injection vulnerability leading to remote code execution (RCE). The exploit crafts a malicious payload to execute arbitrary OS commands, while the scanner checks for vulnerable Handlebars versions and tests for injection.

Description

Versions of handlebars prior to 4.3.0 are vulnerable to Prototype Pollution leading to Remote Code Execution. Templates may alter an Object's __proto__ and __defineGetter__ properties, which may allow an attacker to execute arbitrary code through crafted payloads.

Exploits (1)

nomisec WORKING POC 4 stars
by fazilbaig1 · poc
https://github.com/fazilbaig1/CVE-2019-19919

This repository contains a functional exploit and scanner for CVE-2019-19919, a Handlebars template injection vulnerability leading to remote code execution (RCE). The exploit crafts a malicious payload to execute arbitrary OS commands, while the scanner checks for vulnerable Handlebars versions and tests for injection.

Classification
Working Poc 95%
Attack Type
Rce
Complexity
Moderate
Reliability
Reliable
Target: Handlebars.js (versions below 4.5.3)
No auth needed
Prerequisites: Target application using vulnerable Handlebars.js version · Access to an endpoint that processes Handlebars templates
devstral-2 · analyzed Feb 19, 2026 Full analysis →

References (2)

Core 2
Core References
Third Party Advisory x_refsource_misc
https://www.npmjs.com/advisories/1164
Patch, Third Party Advisory x_refsource_confirm
https://www.tenable.com/security/tns-2021-14

Scores

CVSS v3 9.8
EPSS 0.2475
EPSS Percentile 96.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Details

CWE
CWE-1321
Status published
Products (46)
handlebars.js_project/handlebars.js 1.0.6
handlebars.js_project/handlebars.js 1.0.7
handlebars.js_project/handlebars.js 1.0.8
handlebars.js_project/handlebars.js 1.0.9
handlebars.js_project/handlebars.js 1.0.10
handlebars.js_project/handlebars.js 1.0.11
handlebars.js_project/handlebars.js 1.0.12
handlebars.js_project/handlebars.js 1.1.0
handlebars.js_project/handlebars.js 1.1.1
handlebars.js_project/handlebars.js 1.1.2
... and 36 more
Published Dec 20, 2019
Tracked Since Feb 18, 2026