Hugo versions from v0.162.0 before v0.166.0 contain a case-sensitive validation flaw in the security.http.urls IP-literal deny rule that allows attackers to bypass restrictions. Attackers can use mixed-case URL schemes in resources.GetRemote calls to fetch from restricted IP addresses like localhost.
https://www.vulncheck.com/advisories/hugo-0.162.0-before-0.166.0-ip-literal-deny-rule-bypass
https://github.com/gohugoio/hugo/security/advisories/GHSA-pmrv-x7gp-2rjw
Published: 2026-09-26
Updated: 2026-09-26
Base Score: 7.2
Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C
Severity: High
Base Score: 8.4
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: High
Base Score: 8.6
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.0013