CVE-2023-2142: nunjucks XSS — Fix

Description

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.

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CVSS v3.1 Score

6.1

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
mozilla	nunjucks	< 3.2.4

References

Advisories & Patches

https://github.com/mozilla/nunjucks/security/advisories/GHSA-x77j-w7wf-fjmw

Other References

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

Frequently Asked Questions

What is CVE-2023-2142? +

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. It has a CVSS v3.1 base score of 6.1 (MEDIUM).

How severe is CVE-2023-2142? +

CVE-2023-2142 has a CVSS v3.1 score of 6.1 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2023-2142? +

CVE-2023-2142 affects products from mozilla, specifically: nunjucks. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-2142? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2023-2142