CVE-2026-100691: gohugoio hugo · Cross-site Scripting
Affects gohugoio hugoSource CVE Database V5
Not known to be exploited · CVSS 5.1 Medium : upgrade to 0.166.0 when convenient.
Data as of 9 Nov 2026, 23:24 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.166.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 26 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 10 Nov 2026.
What to do
Upgrade hugo and github.com/gohugoio/hugo to 0.166.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| gohugoiohugo | Affected
| Fixed in
|
Gogithub.com/gohugoio/hugopkg:golang/github.com/gohugoio/hugoOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade to Hugo version 0.166.0 or later, where the lineAnchors value is properly HTML-escaped before being passed to the syntax highlighter. This fix prevents unescaped HTML injection and mitigates the cross-site scripting vulnerability. No other mitigation is required if the upgrade is applied.
Description
A stored cross-site scripting (XSS) vulnerability exists in Hugo versions 0.75.0 through 0.165.x. The issue arises because the syntax highlighter does not properly escape the lineAnchors option before passing it to Chroma, which inserts the value directly into HTML attributes. This allows an attacker to inject arbitrary JavaScript into the generated pages if untrusted Markdown content is published. The vulnerability is fixed in version 0.166.0 by HTML-escaping the lineAnchors value before use.