# CVE-2026-82217: Path traversal in Eclipse Theia

> Attackers can exploit prompt injection in Eclipse Theia Agent Mode to write files outside the workspace, potentially achieving code execution on the backend.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 31 Aug 2026
- **Updated:** 1 Sep 2026
- **Also known as:** GHSA-2qmg-qr8r-hr5c

## What is CVE-2026-82217?

CVE-2026-82217 is a high-severity path traversal vulnerability in Eclipse Theia, published on 31 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

In Eclipse Theia versions 1.73.0 up to but not including 1.75.0, the AI "Agent Mode" file-change tools (writeFileContent, suggestFileContent, and the replacement and state helpers) resolved a model-supplied file path without a workspace-containment check. A crafted relative path such as ../.bashrc, an absolute path, or a ~-expanded path could therefore write or delete files outside the workspace with the privileges of the Theia backend OS user. Because the path argument is influenced by model output, it can be steered through indirect prompt injection, and in Agent Mode writes are applied without a confirmation dialog. Writing to a host-executed file such as a shell startup file or ~/.ssh/authorized_keys can escalate to code execution on the backend.

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

## Which versions are affected by CVE-2026-82217?


## How do I fix CVE-2026-82217?

No fix has been published for CVE-2026-82217 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-82217 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-82217 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-82217 and fix it if it is affected.

What it is: CVE-2026-82217 is a high-severity path traversal vulnerability in Eclipse Theia, published on 31 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-82217 exists.

Affected product: Eclipse Theia. 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-2026-82217/ (Markdown: https://insights.sbomify.com/CVE-2026-82217/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-82217
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-82217
- OSV: https://osv.dev/vulnerability/CVE-2026-82217

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-82217/
Summaries are generated and may contain mistakes; the official description above is the record.