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.

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.

hugo: github.com/gohugoio/hugo: Hugo: Server-Side Request Forgery (SSRF) leading to information disclosure. github.com/gohugoio/hugo: Hugo: Stored Cross-Site Scripting via unescaped code-fence attribute values golang.org/x/image: golang.org/x/image: Denial of Service due to excessive memory allocation when parsing malicious font files github.com/gohugoio/hugo: Hugo: Arbitrary file read via symbolic link sandbox escape github.com/gohugoio/hugo: Hugo: Stored cross-site scripting via unescaped lineAnchors option github.com/gohugoio/hugo: Hugo: Information disclosure via symlinked mount roots github.com/gohugoio/hugo: Hugo: Security restriction bypass via mixed-case URL schemes github.com/gohugoio/hugo: Hugo: Cross-site scripting via unescaped HTML in Org Mode content

Affected: Ubuntu:16.04:LTS: hugo, Ubuntu:18.04:LTS: hugo, Ubuntu:20.04:LTS: hugo, Ubuntu:22.04:LTS: hugo, Ubuntu:Pro:24.04:LTS: hugo, Ubuntu:26.04:LTS: hugo

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.