gohugoio Hugo up to 0.166.x Fallback Resolver js.Build/js.Batch/css.Build path traversal

Summaryinfo

A vulnerability identified as problematic has been detected in gohugoio Hugo up to 0.166.x. This vulnerability affects the function js.Build/js.Batch/css.Build of the component Fallback Resolver. Performing a manipulation results in path traversal. This vulnerability is identified as CVE-2026-109595. The attack can be initiated remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in gohugoio Hugo up to 0.166.x. This affects the function js.Build/js.Batch/css.Build of the component Fallback Resolver. The manipulation with an unknown input leads to a path traversal vulnerability. CWE is classifying the issue as CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. This is going to have an impact on confidentiality. The summary by CVE is:

Hugo from v0.84.0 before v0.167.0 contains a path traversal vulnerability that allows malicious themes or modules to read files outside the project root via ESBuild's fallback resolver in js.Build, js.Batch, and css.Build. Attackers can ship relative imports or symlinks pointing outside the project to bundle any file readable by the build user into published JavaScript or CSS output.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-109595 since 10/12/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1006 for this issue.

Upgrading to version 0.167.0 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• gohugoio

Name

• Hugo

Version

• 0.166

Website

• Product: https://github.com/gohugoio/hugo/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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