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CVE-2026-46409 (GCVE-0-2026-46409)

Vulnerability from cvelistv5 – Published: 2026-08-07 22:11 – Updated: 2026-08-11 01:19
VLAI
Title
OpenYak local API: unauthenticated CSRF chain leads to Remote Code Execution
Summary
OpenYak is a local-first agent runtime for reliable tool-using models, with a desktop workspace built on top. Prior to version 1.1.3, the OpenYak desktop backend binds an HTTP API to `127.0.0.1:<random port>` (commonly 19141) without server-side Origin validation, loopback authentication, or Content-Type enforcement, and with a wildcard CORS policy. Any webpage a user visits while OpenYak is running can issue cross-origin requests to this local server — the browser acts as a proxy into loopback, bypassing OS-level network isolation. Chained, this lets a malicious page execute arbitrary shell commands on the host (RCE) via the build agent with `permission_presets.bash=true`, shut down the service, and exfiltrate chat history and account PII — with no user interaction beyond opening the page. Version 1.1.3 patches the issue.
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-11 01:18 UTC
CWE
  • CWE-94 - Improper Control of Generation of Code ('Code Injection')
  • CWE-306 - Missing Authentication for Critical Function
  • CWE-346 - Origin Validation Error
  • CWE-352 - Cross-Site Request Forgery (CSRF)
  • CWE-942 - Permissive Cross-domain Policy with Untrusted Domains
References
Impacted products
Vendor Product Version CPE status
openyak openyak Affected: < 1.1.3
guessed Create a notification for this product.
Show details on NVD website

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