CVE-2024-34078: XSS (CVSS 6.1)

Description

html-sanitizer is an allowlist-based HTML cleaner. If using `keep_typographic_whitespace=False` (which is the default), the sanitizer normalizes unicode to the NFKC form at the end. Some unicode characters normalize to chevrons; this allows specially crafted HTML to escape sanitization. The problem has been fixed in 2.4.2.

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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)

References

Other References

https://github.com/matthiask/html-sanitizer/commit/48db42fc5143d0140c32d929c46b802f96913550 https://github.com/matthiask/html-sanitizer/security/advisories/GHSA-wvhx-q427-fgh3 https://github.com/matthiask/html-sanitizer/commit/48db42fc5143d0140c32d929c46b802f96913550 https://github.com/matthiask/html-sanitizer/security/advisories/GHSA-wvhx-q427-fgh3 https://lists.debian.org/debian-lts-announce/2024/08/msg00000.html

Frequently Asked Questions

What is CVE-2024-34078? +

html-sanitizer is an allowlist-based HTML cleaner. If using `keep_typographic_whitespace=False` (which is the default), the sanitizer normalizes unicode to the NFKC form at the end. Some unicode characters normalize to chevrons; this allows specially crafted HTML to escape sanitization. The problem has been fixed in 2.4.2. It has a CVSS v3.1 base score of 6.1 (MEDIUM).

How severe is CVE-2024-34078? +

CVE-2024-34078 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.

How do I check if I'm vulnerable to CVE-2024-34078? +

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-2024-34078