GHSA-2cf5-4w76-r9qv
GHSA-2cf5-4w76-r9qv · Arbitrary Code Execution in handlebars
This page contains facts from public vulnerability sources. Check the original advisory before updating.
Versions of `handlebars` prior to 3.0.8 or 4.5.2 are vulnerable to Arbitrary Code Execution. The package's lookup helper fails to properly validate templates, allowing attackers to submit templates that execute arbitrary JavaScript in the system. It can be used to run arbitrary code in a server processing Handlebars templates or on a victim's browser (effectively serving as Cross-Site Scripting). The following template can be used to demonstrate the vulnerability: ```{{#with "constructor"}} {{#with split as |a|}} {{pop (push "alert('Vulnerable Handlebars JS');")}} {{#with (concat (lookup join (slice 0 1)))}} {{#each (slice 2 3)}} {{#with (apply 0 a)}} {{.}} {{/with}} {{/each}} {{/with}} {{/with}} {{/with}}``` ## Recommendation Upgrade to version 3.0.8, 4.5.2 or later.
CVSS 7.3 · High · Fix available
- Published
- Updated
Stack: node
Affected products and versions
handlebars npm
- Affected ranges
- SEMVER: < 3.0.8
Update to 3.0.8
handlebars npm
- Affected ranges
- SEMVER: ≥ 4.0.0, < 4.5.2
Update to 4.5.2