CVE-2026-82533: DeepSeek Harness contains an authentication bypass vulnerability in local HTTP control-plane API
DeepSeek Harness before 0.1.2-alpha.1 contains an authentication bypass vulnerability in its local HTTP control-plane API that allows attackers to gain full agent control by supplying a spoofed Host header, as the server validates only the client-supplied Host header value rather than the actual TCP connection origin.
Published Sep 8, 2026 · Updated Oct 7, 2026
Affected packages
@deepseek-ai/dsh-client-connection
- Ecosystem
- npm
- Affected
- < 0.1.2-alpha.1
- Fixed in
- 0.1.2-alpha.1
- Check
npm ls @deepseek-ai/dsh-client-connection
Advisory details
From the GitHub Advisory Database (CC BY 4.0).
DeepSeek Harness before 0.1.2-alpha.1 contains an authentication bypass vulnerability in its local HTTP control-plane API that allows attackers to gain full agent control by supplying a spoofed Host header, as the server validates only the client-supplied Host header value rather than the actual TCP connection origin. Attackers can exploit this flaw to invoke privileged commands such as commands/execute with danger-full-access permissions, escalate session approval policies to unconfined execution, and retrieve all stored conversations without any credential or API key.
Credited to portyu9.
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-82533
- https://github.com/deepseek-ai/deepseek-harness/commit/3e24087bfaeabe40b58ba2f7b936895b8f93fe27
- https://github.com/deepseek-ai/deepseek-harness/releases/tag/dsh-v0.1.2-alpha.1
- https://www.vulncheck.com/advisories/deepseek-harness-alpha-1-authentication-bypass-via-host-header-spoofing
- https://www.ox.security/blog/cve-2026-82533-deepseek-harness-ai-agent-sandbox-escape
- https://github.com/advisories/GHSA-8m2g-8cgm-3vcp
How this page is made: the data panel comes from the GitHub Advisory Database, CISA’s KEV catalog, the NVD and FIRST EPSS, and updates twice a day. No analysis has been written for this entry yet. Methodology