SB2026042770 - Code Injection in Happy DOM
Published: April 27, 2026
Security Bulletin ID
SB2026042770
Severity
High
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Code Injection (CVE-ID: CVE-2026-33943)
The vulnerability allows a remote attacker to execute arbitrary code.
The vulnerability exists due to improper control of code generation in ECMAScriptModuleCompiler when processing crafted ES module export declarations in HTML content. A remote attacker can inject a specially crafted JavaScript expression to execute arbitrary code.
Exploitation requires JavaScript evaluation to be enabled and user interaction to process attacker-controlled HTML content.
Remediation
Install update from vendor's website.