CVE-2022-31103 json
Improper handling of CSS at-rules in lettersanitizer
published 2022-06-23 4 y ago modified 2026-06-17 4 mo ago also GHSA-7r3r-gq8p-v9jj , EUVD-2022-5983
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.5%
- EPSS 1.5% chance of exploitation in 30 days, percentile 74%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- npm lettersanitizer 1.0.2
- lettersanitizer_project lettersanitizer 1.0.2
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 18 mo ago
Exploit prediction
1.53% chance of exploitation in the next 30 days, higher than 74% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
| GitHub | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | lettersanitizer | <1.0.2 |
1.0.2 |
Affected products
- mat-sz lettersanitizer
Classification
- Weakness
-
- CWE-754 Improper Check for Unusual or Exceptional Conditions
References
-
github.com
/mat-sz/lettersanitizer/commit/96d3dfe2ef0465d47324ed4d13e91ba0816a173f
web, patch, third-party-advisory
-
github.com
/mat-sz/lettersanitizer/security/advisories/GHSA-7r3r-gq8p-v9jj
web, third-party-advisory
-
github.com
/mat-sz/react-letter/issues/17
web, issue-tracking, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2022-31103
advisory
-
github.com
/mat-sz/lettersanitizer
package
Sources
- CVE List CVE-2022-31103
- GitHub Advisory GHSA-7r3r-gq8p-v9jj
- NVD CVE-2022-31103
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.