# CVE-2026-101078: deepseek-ai deepseek-harness improper isolation in Landlock Backend

Source: https://junglewise.ai/threats/cve-2026-101078-a-vulnerability-has-been-found-in-deepseek-ai-deepseek-harness  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-28. Updated: 2026-09-28  
License: CC BY 4.0 with a link back

CVE-2026-101078 · Severity: medium · CVSS 6.3 · Published 2026-09-28

deepseek-harness is a sandboxing framework used to safely isolate untrusted code execution. A flaw in its Landlock-based sandbox backend fails to properly compartmentalize processes, potentially allowing a local attacker to escape the sandbox and gain unauthorized access to the host system. The vulnerability can be exploited by an attacker with local access to the sandboxed environment.

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

## Quick answers

**Is CVE-2026-101078 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-101078 being exploited in the wild.

**How severe is CVE-2026-101078?** Medium severity, with a CVSS score of 6.3, published 28 September 2026.

**Which products and versions are affected?** Deepseek-Ai Deepseek-Harness up to 0.1.7-rc.2.

**Is there a fix for CVE-2026-101078?** 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-2026-101078 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-101078?** Check whether you run Deepseek-Ai 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 Landlock Backend component (profiles.ts) and results in improper isolation or compartmentalization of sandboxed processes. An attacker with local access can exploit this flaw through mount/remount operations to escape the sandbox restrictions. A patch is available and should be applied immediately.

## Affected products

- deepseek-ai deepseek-harness up to 0.1.7-rc.2

## Timeline

- 2026-09-28: disclosed: Vulnerability disclosed publicly
- 2026-09-28: other: Vendor contacted but did not respond

## References

- [https://github.com/Ruoyyy/My_vulnerable/blob/main/SECURITY-MOUNT-ESCAPE.en.md](https://github.com/Ruoyyy/My_vulnerable/blob/main/SECURITY-MOUNT-ESCAPE.en.md)
- [https://vuldb.com/cve/CVE-2026-101078](https://vuldb.com/cve/CVE-2026-101078)

## Related threats

- [DeepSeek Harness sandbox escape via injected host-realm functions](https://junglewise.ai/threats/cve-2026-108789-a-vulnerability-was-identified-in-deepseek-ai-deepseek-harness)
- [deepseek-harness sandbox escape via Profile argument](https://junglewise.ai/threats/cve-2026-108788-a-vulnerability-was-determined-in-deepseek-ai-deepseek-harness)