CVE-2022-31103

Name: CVE-2022-31103
Creator: NVD / NIST
Published: 2022-06-27T23:15:08.17+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.38%

Last modified Jun 17, 2026

CVE-2022-31103 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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`. EPSS estimates a 1.38% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

1.38%

68.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-754

Affected Software

Vendor	Product	Versions
Lettersanitizer Project	Lettersanitizer	< 1.0.2

References

https://github.com/mat-sz/lettersanitizer/commit/96d3dfe2ef0465d47324ed4d13e91ba0816a173fPatch, Third Party Advisory
https://github.com/mat-sz/lettersanitizer/security/advisories/GHSA-7r3r-gq8p-v9jjThird Party Advisory
https://github.com/mat-sz/react-letter/issues/17Issue Tracking, Third Party Advisory
https://github.com/mat-sz/lettersanitizer/commit/96d3dfe2ef0465d47324ed4d13e91ba0816a173fPatch, Third Party Advisory
https://github.com/mat-sz/lettersanitizer/security/advisories/GHSA-7r3r-gq8p-v9jjThird Party Advisory
https://github.com/mat-sz/react-letter/issues/17Issue Tracking, Third Party Advisory

Timeline

Published: Jun 27, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2022-31103?

How severe is CVE-2022-31103?

CVE-2022-31103 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.38% probability of exploitation in the next 30 days.

How do I fix CVE-2022-31103?

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.

Are you affected by CVE-2022-31103?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST