{"id":"CVE-2026-46409","aliases":["EUVD-2026-54715","GHSA-ccxp-q2w5-27jw"],"status":"published","title":"OpenYak local API: unauthenticated CSRF chain leads to Remote Code Execution","description":"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:\u003crandom port\u003e` (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.","severity":{"version":"3.1","score":9.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00282,"percentile":0.20844,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-306","CWE-346","CWE-352","CWE-94","CWE-942"],"published":"2026-08-07T22:11:57Z","modified":"2026-10-28T02:30:45Z","products":[{"vendor":"openyak","product":"openyak"}],"references":[{"url":"https://github.com/openyak/openyak/security/advisories/GHSA-ccxp-q2w5-27jw","tags":["x_refsource_CONFIRM","advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46409.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-46409","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-46409","title":"OpenYak local API: unauthenticated CSRF chain leads to Remote Code Execution","description":"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:\u003crandom port\u003e` (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.","status":"published","published":"2026-08-07T22:11:57.765Z","modified":"2026-08-11T01:19:03.951Z","cvss":[{"version":"3.1","score":9.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H","level":"critical","assessor":"cna"}],"cwes":["CWE-94","CWE-306","CWE-346","CWE-352","CWE-942"],"updated_at":"2026-11-02T13:46:55.086623Z"}],"euvd":[{"id":"EUVD-2026-54715","description":"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:\u003crandom port\u003e` (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.","status":"published","published":"2026-08-07T22:11:57Z","modified":"2026-08-11T01:19:03Z","cvss":[{"version":"3.1","score":9.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T18:02:00.742322Z"}],"nvd":[{"id":"CVE-2026-46409","description":"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:\u003crandom port\u003e` (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.","status":"published","published":"2026-08-07T23:17:03.243Z","modified":"2026-09-18T20:09:01.757Z","cvss":[{"version":"3.1","score":9.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H","level":"critical","assessor":"secondary"}],"cwes":["CWE-94","CWE-306","CWE-346","CWE-352","CWE-942"],"updated_at":"2026-11-02T14:12:35.743275Z"}],"osv":[{"id":"CVE-2026-46409","title":"OpenYak local API: unauthenticated CSRF chain leads to Remote Code Execution","description":"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:\u003crandom port\u003e` (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.","status":"published","published":"2026-08-07T22:11:57.765Z","modified":"2026-10-28T02:30:45.404700534Z","cvss":[{"version":"3.1","score":9.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-306","CWE-346","CWE-352","CWE-94","CWE-942"],"updated_at":"2026-11-02T15:45:05.870292Z"}]}}