CVE-2024-34078

html-sanitizer allows arbitrary HTML present after sanitization because of unicode normalization

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.

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.04%
Affected: matthiask html-sanitizer
Published at:
Updated at:

References

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

Frequently Asked Questions

What is the severity of CVE-2024-34078?
CVE-2024-34078 has been scored as a medium severity vulnerability.
How to fix CVE-2024-34078?
To fix CVE-2024-34078, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2024-34078 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-34078 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2024-34078?
CVE-2024-34078 affects matthiask html-sanitizer.
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