Hugo before 0.166.0 Stored XSS via lineAnchors code block option
Hugo versions 0.75.0 through 0.165.x contain a stored cross-site scripting vulnerability: the syntax highlighter does not escape the `lineAnchors` option before passing it to Chroma, which writes the value verbatim into the `id` and `href` attributes of the generated line-number markup. A crafted `lineAnchors` value supplied as a Markdown code fence attribute (or passed to the `highlight` template function) results in unescaped HTML in the rendered page, allowing arbitrary JavaScript to execute in the browsers of visitors to the generated site. This affects sites that build and publish Markdown from untrusted contributors; Hugo's security model otherwise considers content trusted input. Fixed in 0.166.0, where the `lineAnchors` value is HTML-escaped before being passed to Chroma.
CVE-2026-100691
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-100691
hugo
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "gohugoio",
"product": "hugo",
"versions": [
{
"status": "affected",
"version": "0.75.0",
"lessThan": "0.166.0",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "0.166.0",
"versionType": "semver"
}
],
"packageURL": "pkg:golang/github.com/gohugoio/hugo",
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-100691
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #3275 · Revision 1
- Added to Heist Feed
- Publisher date