handlebars.js up to 4.7.9 Code Generation code-gen.js Handlebars.precompile cross site scripting

Summaryinfo

A vulnerability classified as problematic has been found in handlebars.js up to 4.7.9. This affects the function Handlebars.precompile of the file lib/handlebars/compiler/code-gen.js of the component Code Generation. The manipulation leads to cross site scripting. This vulnerability is referenced as CVE-2026-106444. Remote exploitation of the attack is possible. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in handlebars.js up to 4.7.9 and classified as problematic. This issue affects the function Handlebars.precompile of the file lib/handlebars/compiler/code-gen.js of the component Code Generation. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. The summary by CVE is:

Handlebars provides the power necessary to let users build semantic templates. From 4.0.0 until 4.7.10, Handlebars.precompile() uses quotedString() in lib/handlebars/compiler/code-gen.js to emit static template text into generated JavaScript without escaping sequences that terminate an enclosing HTML script element. When an application precompiles attacker-controlled template text and embeds the generated source directly in an inline script element, a closing script delimiter can end the element and cause following attacker-controlled markup to be parsed and executed. Ordinary server-side rendering and precompiled templates served as external JavaScript files are not affected. This issue is fixed in version 4.7.10.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-106444 since 10/06/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

Upgrading to version 4.7.10 eliminates this vulnerability.

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Productinfo

Type

• JavaScript Library

Name

• handlebars.js

Version

• 4.7.0
• 4.7.1
• 4.7.2
• 4.7.3
• 4.7.4
• 4.7.5
• 4.7.6
• 4.7.7
• 4.7.8
• 4.7.9

CPE 2.3info

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CPE 2.2info

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