# CVE-2026-93712: Dancer2 versions from 2.1.0 before 2.2.0 for Perl serve files from outside public_dir via relative path segments in the File route handler.

> Attackers can read arbitrary files outside the public directory if the File route handler is enabled and static handling is disabled.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 22 Sep 2026
- **Updated:** 22 Sep 2026
- **Also known as:** DEBIAN-CVE-2026-93712, GHSA-6xw8-v24c-m783, GHSA-fq22-f6q5-wv3x, UBUNTU-CVE-2026-93712

## What is CVE-2026-93712?

CVE-2026-93712 is a high-severity path traversal vulnerability, published on 22 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Dancer2 versions from 2.1.0 before 2.2.0 for Perl serve files from outside public_dir via relative path segments in the File route handler.

The handler joins the request path onto public_dir without collapsing relative segments, and checks only that the result is a readable regular file. A request for `/../outside.txt` escapes public_dir, and percent-encoding the dots reaches the same file.

The handler is off by default. An application is affected once it names File in route_handlers and sets static_handler to 0, which otherwise refuses a dot segment before the route runs.

Any file the worker process can read is served to an unauthenticated request, including the application's config.yml above public_dir.

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

## Which versions are affected by CVE-2026-93712?


## How do I fix CVE-2026-93712?

Upgrade to a fixed version.

## Is CVE-2026-93712 being exploited?

There is no known exploitation of CVE-2026-93712 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-93712 and fix it if it is affected.

What it is: CVE-2026-93712 is a high-severity path traversal vulnerability, published on 22 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-93712 in the wild and no public exploit code.

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-2026-93712/ (Markdown: https://insights.sbomify.com/CVE-2026-93712/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-93712
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-93712
- OSV: https://osv.dev/vulnerability/CVE-2026-93712

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-93712/
Summaries are generated and may contain mistakes; the official description above is the record.