In Nunjucks versions prior to version 3.2.4, it was possible to bypass the restrictions which are provided by the autoescape functionality. If there are two user-controlled parameters on the same line used in the views, it was possible to inject cross site scripting payloads using the backslash \ character.

Affected: npm: nunjucks

### Impact In Nunjucks versions prior to version 3.2.4, it was possible to bypass the restrictions which are provided by the autoescape functionality. If there are two user-controlled parameters on the same line used in the views, it was possible to inject cross site scripting payloads using the backslash `\` character.

#### Example If the user-controlled parameters were used in the views similar to the following: ``` <script> let testObject = { lang: '{{ lang }}', place: '{{ place }}' }; </script> ```

It is possible to inject XSS payload using the below parameters: ``` https://<application-url>/?lang=jp\&place=};alert(document.domain)// ```

### Patches The issue was patched in version 3.2.4.

### References

- https://bugzilla.mozilla.org/show_bug.cgi?id=1825980

Affected: Ubuntu:24.04:LTS: node-nunjucks, Ubuntu:25.10: node-nunjucks, Ubuntu:26.04:LTS: node-nunjucks

In Nunjucks versions prior to version 3.2.4, it was possible to bypass the restrictions which are provided by the autoescape functionality. If there are two user-controlled parameters on the same line used in the views, it was possible to inject cross site scripting payloads using the backslash \ character.