mathlive's Lack of Escaping of HTML allows for XSS

published 2026-07-29 3 mo ago modified 2026-10-24 15 d ago also GHSA-fm7p-gw32-828p , EUVD-2026-50421

cvss: 6.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 22%
public exploits: 0; none known

MathLive provides web components for math display and input. Prior to 0.110.0, MathLive fails to escape text-mode content in \text{} and \mbox{} commands in Box.toMarkup at src/core/box.ts, in xmlEscape, scanText, and text-mode output in src/formats/atom-to-math-ml.ts, and through convertLatexToMarkup, convertLatexToMathMl, <math-span>, <math-div>, and the default identity MathfieldElement.createHTML, allowing malicious input to run arbitrary JavaScript when rendered. This issue is fixed in version 0.110.0.

Patch / fix

fixed in 1 links 1

npm mathlive 0.110.0

github.com/arnog/mathlive@5fe1c46 commit

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 3 mo ago (2026-07-29)

Exploit prediction

0.30% chance of exploitation in the next 30 days, higher than 22% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/arnog/mathlive/security/advisories/GHSA-fm7p-gw32-828p referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
GitHub	3.1	6.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

Affected packages

ecosystem	package	affected	fixed in
npm	mathlive	<0.110.0	0.110.0

Affected products

arnog mathlive

Classification

Weakness

CWE-116 Improper Encoding or Escaping of Output

References

Sources

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.

Summary