SSRF in Gohugo Hugo
CVE-2026-58404
Hugo is a static site generator. From v0.162.0 through v0.163.0, the default security.http.urls policy denies requests to loopback, internal, and cloud-metadata IPv4 literals, but the deny rule only matched dotted-decimal notation, so alternate IPv4 encodings of the same addresses, including integer, hex, or octal, passed the policy. When a template passes an untrusted or data-derived URL to resources.GetRemote and the host platform uses the cgo system resolver, these encodings resolve to the blocked address, allowing build-time server-side requests to loopback and internal services, including the cloud-metadata endpoint in hosted or CI builds; the same check is reused on redirects, so the gap also applies to each redirect hop. This issue is fixed in v0.163.1.
Vulnerability class: SSRF (Server-Side Request Forgery)
EPSS: 0.002 (11.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:N/A:N.
Affected products
- Gohugo Hugo
- Gohugoio Hugo — versions >= v0.162.0, < v0.163.1
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Mitigation, Vendor Advisory)
- security-advisories@github.com (x_refsource_MISC, Issue Tracking)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2026-58404?
- CVE-2026-58404 is a medium-severity vulnerability in Gohugo Hugo, classified under Server-Side Request Forgery (SSRF). CVSS score: 6.8/10. Published 2026-07-06.
- How severe is CVE-2026-58404?
- Medium severity. CVSS v3 base score is 6.8 out of 10.