Cross-site Scripting (XSS)

published 2022-07-25 4 y ago modified 2026-06-17 4 mo ago also GHSA-wfvx-fx73-3rfj , EUVD-2022-6435

cvss: 7.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.6%; EPSS 0.6% chance of exploitation in 30 days, percentile 49%
public exploits: 0; none known

This affects all versions of package markdown-it-toc. The title of the generated toc and the contents of the header are not escaped.

Exploit prediction

0.61% chance of exploitation in the next 30 days, higher than 49% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

security.snyk.io https://security.snyk.io/vuln/SNYK-JS-MARKDOWNITTOC-1044067 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:U/RC:C
CNA	3.1	7.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
NVD	3.1	6.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
GitHub	3.1	6.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected packages

ecosystem	package	affected	fixed in
npm	markdown-it-toc	<=1.1.0	no fix listed

Affected products

n/a markdown-it-toc

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

security.snyk.io /vuln/SNYK-JS-MARKDOWNITTOC-1044067
web, exploit, third-party-advisory
nvd.nist.gov /vuln/detail/CVE-2020-28455
advisory

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