CVE-2026-33916

Handlebars provides the power necessary to let users build semantic templates. In versions 4.0.0 through 4.7.8, resolvePartial in the Handlebars runtime resolves partial names via a plain property lookup on options.partials without guarding against prototype-chain traversal. When Object.prototype...

CVE-2026-33916

Handlebars provides the power necessary to let users build semantic templates. In versions 4.0.0 through 4.7.8, resolvePartial in the Handlebars runtime resolves partial names via a plain property lookup on options.partials without guarding against prototype-chain traversal. When Object.prototype...

CVE-2026-33916 Handlebars.js has Prototype Pollution Leading to XSS through Partial Template Injection

Handlebars provides the power necessary to let users build semantic templates. In versions 4.0.0 through 4.7.8, resolvePartial in the Handlebars runtime resolves partial names via a plain property lookup on options.partials without guarding against prototype-chain traversal. When Object.prototype...

Handlebars.js has JavaScript Injection via AST Type Confusion when passing an object as dynamic partial

Summary A crafted object placed in the template context can bypass all conditional guards in resolvePartial and cause invokePartial to return undefined. The Handlebars runtime then treats the unresolved partial as a source that needs to be compiled, passing the crafted object to env.compile...

PT-2026-28572

Name of the Vulnerable Software and Affected Versions Handlebars versions 4.0.0 through 4.7.8 Description Handlebars allows users to build semantic templates. A crafted object placed in the template context can bypass conditional guards in the resolvePartial function, causing invokePartial to...

Prototype Pollution

Overview handlebars is an extension to the Mustache templating language. Affected versions of this package are vulnerable to Prototype Pollution via the resolvePartial function. An attacker can inject malicious scripts into rendered output by polluting Object.prototype with a key matching a parti...