CVE-2024-34078: html-sanitizer is an allowlist-based HTML cleaner. If using `keep_typographic_whitespace=False` (which is the default), the sanitizer normalizes unico...

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.

Metrics

CVSS 3.1

6.1/10

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

EPSS Probability

0.55%

41.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

References

Timeline

Published: May 6, 2024
Last Modified: Jun 17, 2026
Status: Deferred

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.

How severe is CVE-2024-34078?

CVE-2024-34078 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 0.55% probability of exploitation in the next 30 days.

How do I fix CVE-2024-34078?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.