CVE-2022-31103 - CVE House
Back to Database
Status published High CVE-2022-31103

Improper handling of CSS at-rules in lettersanitizer

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

THREAT MONITOR

Am I Vulnerable?

Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2022-31103

Credits & Attribution

No credits recorded in the NVD database.

References

Affected Vendor

Affected Software

lettersanitizer
Vulnerable Versions:
< 1.0.2

Timeline

Official Publish: June 27th, 2022
Last Modified: April 23rd, 2025
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

CWE-754

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1499 Endpoint Denial of Service
Impact
T1562 Impair Defenses
Defense Evasion
T1005 Data from Local System
Collection