# CVE-2026-56122: Winstone Servlet Engine 0.9.10 Path Traversal via HTTP Request Paths

> Unauthenticated attackers can read arbitrary files outside the webroot via path traversal in Winstone Servlet Engine HTTP requests.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 25 Jun 2026
- **Updated:** 25 Jun 2026
- **Also known as:** GHSA-qf2j-8858-jvcv

## What is CVE-2026-56122?

CVE-2026-56122 is a high-severity path traversal vulnerability in rickknowles Winstone Servlet Container, published on 25 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Winstone Servlet Engine through 0.9.10 contains a path traversal vulnerability that allows unauthenticated attackers to read arbitrary files by sending HTTP GET requests with dot-dot-slash sequences that are not sanitized when serving static files from the configured webroot. Attackers can traverse outside the webroot directory using traversal-prefixed paths in a single HTTP request to read any file accessible to the servlet engine process, including sensitive system files when the service runs with elevated privileges.

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

## Which versions are affected by CVE-2026-56122?


## How do I fix CVE-2026-56122?

No fix has been published for CVE-2026-56122 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-56122 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-56122 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-56122 and fix it if it is affected.

What it is: CVE-2026-56122 is a high-severity path traversal vulnerability in rickknowles Winstone Servlet Container, published on 25 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-56122 exists.

Affected product: rickknowles Winstone Servlet Container. 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-2026-56122/ (Markdown: https://insights.sbomify.com/CVE-2026-56122/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-56122
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-56122
- OSV: https://osv.dev/vulnerability/CVE-2026-56122

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-56122/
Summaries are generated and may contain mistakes; the official description above is the record.