KaTeX's maxExpand bypassed by \edef
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-674.
Summary
KaTeX is a JavaScript library for TeX math rendering on the web. KaTeX users who render untrusted mathematical expressions could encounter malicious input using `\edef` that causes a near-infinite loop, despite setting `maxExpand` to avoid such loops. This can be used as an availability attack, where e.g. a client rendering another user's KaTeX input will be unable to use the site due to memory overflow, tying up the main thread, or stack overflow. Upgrade to KaTeX v0.16.10 to remove this vulnerability.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| KaTeX | KaTeX | 0.12.0 to before 0.16.10 | 0.16.10 | Patch available | CNA |
| — | katex (npm) | 0.12.0 to before 0.16.10 | 0.16.10 | Patch available | GHSA-64fm-8hw2-v72w |
- KaTeX VendorKaTeX Affected 0.12.0 to before 0.16.10 Fixed in 0.16.10 Patch available CNA
- katex (npm) Vendor— Affected 0.12.0 to before 0.16.10 Fixed in 0.16.10 Patch available GHSA-64fm-8hw2-v72w
Remediation
- Fix · CNA KaTeX (KaTeX) Fixed in 0.16.10
- Fix · GHSA-64fm-8hw2-v72w katex (npm) Fixed in 0.16.10 Advisory →
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2024-28243
- 2026-10-03 Alias added: GHSA-64fm-8hw2-v72w
References
Advisory 2
More Katex vulnerabilities
- TI-2024-18803 KaTeX's maxExpand bypassed by Unicode sub/superscripts CVSS 3.1MEDIUM 6.5
- TI-2025-16992 \htmlData does not validate attribute names in KaTeX CVSS 3.1HIGH 7.2
- TI-2024-18804 KaTeX's \includegraphics does not escape filename CVSS 3.1MEDIUM 6.3
- TI-2024-18805 KaTeX is missing normalization of the protocol in URLs allows bypassing forbidden protocols CVSS 3.1MEDIUM 5.5
Sources
- CVE-2024-28243 · CVE Program
- CVE-2024-28243 · NVD
- FIRST EPSS
- GHSA-64fm-8hw2-v72w · GitHub Advisory Database · CC BY 4.0
- CVE-2024-28243 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences