{"id":"CVE-2026-33940","revision":"c8cfe272a00f4251bf26103e3ed94828","records":[{"revision":"c8cfe272a00f4251bf26103e3ed94828","observedAt":"2026-10-27T09:03:00.507+00:00","statement":{"source":"nvd","id":"CVE-2026-33940","aliases":[],"title":"Handlebars provides the power necessary to let users build semantic templates. In versions 4.0.0 through 4.7.8, a crafted object placed in the template context can bypass all conditional guards in `resolvePartial()` and cause `invokePartial…","description":"Handlebars provides the power necessary to let users build semantic templates. In versions 4.0.0 through 4.7.8, 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()`. Because the object is a valid Handlebars AST containing injected code, the generated JavaScript executes arbitrary commands on the server. The attack requires the adversary to control a value that can be returned by a dynamic partial lookup. Version 4.7.9 fixes the issue. Some workarounds are available. First, use the runtime-only build (`require('handlebars/runtime')`). Without `compile()`,  the fallback compilation path in `invokePartial` is unreachable. Second, sanitize context data before rendering: Ensure no value in the context is a non-primitive  object that could be passed to a dynamic partial. Third, avoid dynamic partial lookups (`{{> (lookup ...)}}`) when context data is user-controlled.","state":0,"publishedAt":"2026-03-27T22:16:21.03+00:00","modifiedAt":"2026-10-26T22:10:00.163+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · security-advisories@github.com · Secondary","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.1,"severity":"HIGH"},{"system":"CVSS 3.1 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c · Secondary","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.1,"severity":"HIGH"}],"references":["https://github.com/handlebars-lang/handlebars.js/commit/68d8df5a88e0a26fe9e6084c5c6aaebe67b07da2","https://github.com/handlebars-lang/handlebars.js/releases/tag/v4.7.9","https://github.com/handlebars-lang/handlebars.js/security/advisories/GHSA-xhpv-hc6g-r9c6","https://access.redhat.com/errata/RHSA-2026:10175","https://access.redhat.com/errata/RHSA-2026:34342","https://access.redhat.com/security/cve/CVE-2026-33940","https://bugzilla.redhat.com/show_bug.cgi?id=2452521","https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33940.json"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-33940","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Modified","weaknesses":["CWE-94","CWE-843"],"productCriteria":["cpe:2.3:a:handlebarsjs:handlebars:*:*:*:*:*:node.js:*:*"],"sourceDates":{"published":"2026-03-27T22:16:21.030","lastModified":"2026-10-26T22:10:00.163"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-33940","identifiers":["CVE-2026-33940"]},"retained":false,"historicalAffected":[]}],"coverage":[]}