9.8

CVE-2026-33937

Exploit

Handlebars.js has JavaScript Injection via AST Type Confusion

Handlebars provides the power necessary to let users build semantic templates. In versions 4.0.0 through 4.7.8, `Handlebars.compile()` accepts a pre-parsed AST object in addition to a template string. The `value` field of a `NumberLiteral` AST node is emitted directly into the generated JavaScript without quoting or sanitization. An attacker who can supply a crafted AST to `compile()` can therefore inject and execute arbitrary JavaScript, leading to Remote Code Execution on the server. Version 4.7.9 fixes the issue. Some workarounds are available. Validate input type before calling `Handlebars.compile()`; ensure the argument is always a  `string`, never a plain object or JSON-deserialized value. Use the Handlebars runtime-only build (`handlebars/runtime`) on the server if templates are pre-compiled at build time; `compile()` will be unavailable.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Handlebarsjs ≫ Handlebars SwPlatformnode.js Version >= 4.0.0 < 4.7.9
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 1.78% 0.756
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
security-advisories@github.com 9.8 3.9 5.9
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
0b0ca135-0b70-47e7-9f44-1890c2a1c46c 9.8 3.9 5.9
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE-843 Access of Resource Using Incompatible Type ('Type Confusion')

The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.

CWE-94 Improper Control of Generation of Code ('Code Injection')

The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.

https://github.com/handlebars-lang/handlebars.js/commit/68d8df5a88e0a26fe9e6084c5c6aaebe67b07da2
Patch
https://github.com/handlebars-lang/handlebars.js/releases/tag/v4.7.9
Release Notes
https://github.com/handlebars-lang/handlebars.js/security/advisories/GHSA-2w6w-674q-4c4q
Vendor Advisory
Exploit
https://access.redhat.com/errata/RHSA-2026:10175
https://access.redhat.com/security/cve/CVE-2026-33937
https://bugzilla.redhat.com/show_bug.cgi?id=2452523
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33937.json
https://access.redhat.com/errata/RHSA-2026:34342