GHSA-r46f-3rpw-hxrv
GHSA-r46f-3rpw-hxrv is a Server-Side Request Forgery (SSRF) vulnerability in github.com/gohugoio/hugo. O3 Security confirms whether GHSA-r46f-3rpw-hxrv is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Hugo: security.http.urls deny rules bypassed by alternate IPv4 encodings (SSRF)
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
github.com/gohugoio/hugoReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Impact
The default security.http.urls policy denies requests to loopback, internal,
and cloud-metadata IPv4 literals (e.g. http://127.0.0.1/,
http://169.254.169.254/). The deny rule only matched dotted-decimal notation,
so alternate IPv4 encodings of the same addresses — integer, hex, or octal,
which contain no dot — passed the policy:
http://2130706433/→127.0.0.1http://2852039166/→169.254.169.254(cloud metadata)http://0x7f000001/,http://017700000001/,http://0/
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/CI builds. The same check is reused on
redirects, so the gap also applies to each redirect hop.
This affects sites that rely on security.http.urls as a security boundary
while fetching attacker-influenced remote URLs; it does not affect sites that
fully trust the URLs they fetch.
Patches
Fixed in v0.163.1. Integer/hex/octal IPv4 hosts are now canonicalized to dotted-decimal before the policy is applied, so every encoding of an address is treated alike. No configuration change is required.
Workarounds
Avoid passing untrusted URLs to resources.GetRemote, or
tighten security.http.urls to an explicit allow-list of trusted hosts.
Affected versions
v0.162.0 – v0.163.0 (patched in v0.163.1).
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/gohugoio/hugo | ≥ 0.162.0&&< 0.163.1 | 0.163.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/gohugoio/hugo. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/gohugoio/hugo to 0.163.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-r46f-3rpw-hxrv is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-r46f-3rpw-hxrv is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-r46f-3rpw-hxrv. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-r46f-3rpw-hxrv in your dependencies?
O3 detects GHSA-r46f-3rpw-hxrv across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.