# CVE-2026-109595: Hugo v0.84.0 before v0.167.0 Path Traversal via js.Build ESBuild Resolver

> Malicious themes or modules can read files outside the project root via ESBuild's resolver, exposing sensitive data to attackers.

- **Severity:** Medium 6.7 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 12 Oct 2026
- **Updated:** 15 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-109595, GHSA-6cfm-3xc5-q3r5, GHSA-r4xx-89rf-5424, MINI-3wg4-wvxp-4q4w, MINI-vwgp-qhm4-65q4, UBUNTU-CVE-2026-109595

## What is CVE-2026-109595?

CVE-2026-109595 is a medium-severity path traversal vulnerability in gohugoio hugo, published on 12 Oct 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

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.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-109595?


## How do I fix CVE-2026-109595?

Upgrade to a fixed version.

## Is CVE-2026-109595 being exploited?

There is no known exploitation of CVE-2026-109595 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-109595 and fix it if it is affected.

What it is: CVE-2026-109595 is a medium-severity path traversal vulnerability in gohugoio hugo, published on 12 Oct 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-109595 in the wild and no public exploit code.

Affected product: gohugoio hugo. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-109595/ (Markdown: https://insights.sbomify.com/CVE-2026-109595/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-109595
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-109595
- OSV: https://osv.dev/vulnerability/CVE-2026-109595

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-109595/
Summaries are generated and may contain mistakes; the official description above is the record.