# CVE-2026-116367: DeepSeek Harness sandbox issue in createContext

Source: https://junglewise.ai/threats/cve-2026-116367-a-vulnerability-was-found-in-deepseek-harness-up-to-0-1-0-rc-5  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-26. Updated: 2026-10-26  
License: CC BY 4.0 with a link back

CVE-2026-116367 · Severity: medium · CVSS 6.3 · Published 2026-10-26

DeepSeek Harness is a development framework that runs code in isolated sandbox environments. A vulnerability in its context creation function allows attackers to break out of the sandbox and execute code outside the intended isolation boundary, potentially compromising the host system.

Technologies: [DeepSeek Harness](https://junglewise.ai/threats/technologies/deepseek-harness-1). Vendors: [DeepSeek](https://junglewise.ai/threats/vendors/deepseek).

## Quick answers

**Is CVE-2026-116367 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-116367 being exploited in the wild.

**How severe is CVE-2026-116367?** Medium severity, with a CVSS score of 6.3, published 26 October 2026.

**Which products and versions are affected?** DeepSeek Harness up to 0.1.0-rc.5.

**Is there a fix for CVE-2026-116367?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-116367 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-116367?** Check whether you run DeepSeek Harness at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability exists in the createContext function of the cordis-host-runner component (packages/extensions/cordis-host-runner/src/sandbox.ts) and results in a sandbox escape. The attack is remotely exploitable and does not require authentication or user interaction, allowing an attacker to break sandbox isolation and gain execution on the host system.

## Affected products

- DeepSeek Harness up to 0.1.0-rc.5

## Timeline

- 2026-10-26: disclosed

## References

- [https://vuldb.com/cve/CVE-2026-116367](https://vuldb.com/cve/CVE-2026-116367)
- [https://vuldb.com/submit/1012736](https://vuldb.com/submit/1012736)

## Related threats

- [DeepSeek Harness auth bypass in web RPC control plane](https://junglewise.ai/threats/cve-2026-82033-deepseek-harness-prior-to-0-1-2-alpha-2-and-specifically-commit)
- [DeepSeek Harness improper authorization in browser auth](https://junglewise.ai/threats/cve-2026-116368-a-vulnerability-was-determined-in-deepseek-harness-up-to-0-2-0)