CVE-2022-31103

Improper handling of CSS at-rules in lettersanitizer

Description

lettersanitizer is a DOM-based HTML email sanitizer for in-browser email rendering. All versions of lettersanitizer below 1.0.2 are affected by a denial of service issue when processing a CSS at-rule `@keyframes`. This package is depended on by [react-letter](https://github.com/mat-sz/react-letter), therefore everyone using react-letter is also at risk. The problem has been patched in version 1.0.2.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.12%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: mat-sz lettersanitizer
Published at:
Updated at:

References

Link Tags
https://github.com/mat-sz/lettersanitizer/security/advisories/GHSA-7r3r-gq8p-v9jj third party advisory
https://github.com/mat-sz/react-letter/issues/17 third party advisory issue tracking
https://github.com/mat-sz/lettersanitizer/commit/96d3dfe2ef0465d47324ed4d13e91ba0816a173f third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2022-31103?
CVE-2022-31103 has been scored as a high severity vulnerability.
How to fix CVE-2022-31103?
To fix CVE-2022-31103, 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-2022-31103 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2022-31103 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-2022-31103?
CVE-2022-31103 affects mat-sz lettersanitizer.
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