Is CVE-2026-100693 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-100693 being exploited in the wild.

How severe is CVE-2026-100693?

High severity, with a CVSS score of 8.4, published 26 September 2026.

Which products and versions are affected?

Gohugoio Hugo >=0.162.0, <0.166.0.

Is there a fix for CVE-2026-100693?

A patch was published on 2026-09-26: Version 0.166.0 released with fix Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-100693 attacked?

It is attacked with local access, in a software library.

Am I affected by CVE-2026-100693?

Check whether you run Gohugoio Hugo at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-100693: Hugo case-sensitive URL scheme validation bypass in security.http.urls

Q: Is there a fix for CVE-2026-100693?

A patch was published on 2026-09-26: Version 0.166.0 released with fix Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-100693 attacked?

It is attacked with local access, in a software library.

Q: Am I affected by CVE-2026-100693?

Check whether you run Gohugoio Hugo at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-100693 · Severity: high · CVSS 8.4 · Published 2026-09-26

Hugo is a static site generator used to build websites. In versions 0.162.0 through 0.165.x, attackers can bypass security restrictions on outbound network requests by using mixed-case URL schemes (like "HTTP://" instead of "http://"). This allows an attacker to fetch content from restricted internal IP addresses like localhost, potentially accessing sensitive configuration data or internal services.

Technologies: Gohugoio Hugo. Vendors: Gohugoio.

Quick answers

Is CVE-2026-100693 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-100693 being exploited in the wild.
How severe is CVE-2026-100693?: High severity, with a CVSS score of 8.4, published 26 September 2026.
Which products and versions are affected?: Gohugoio Hugo >=0.162.0, <0.166.0.
Is there a fix for CVE-2026-100693?: A patch was published on 2026-09-26: Version 0.166.0 released with fix Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-100693 attacked?: It is attacked with local access, in a software library.
Am I affected by CVE-2026-100693?: Check whether you run Gohugoio Hugo at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability is a case-sensitivity flaw (CWE-178) in the default IP-literal deny rule of security.http.urls, which validates URLs in resources.GetRemote calls. The deny rule failed to normalize URL scheme casing before validation, so an uppercase or mixed-case scheme bypassed the filter. An attacker who can control URLs passed to resources.GetRemote can exploit this to reach restricted IP addresses without authentication.

Affected products

gohugoio Hugo >=0.162.0, <0.166.0

Timeline

2026-09-26: disclosed
2026-09-26: patched: Version 0.166.0 released with fix

References

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