{"id":"CVE-2026-59809","aliases":["EUVD-2026-64267","GHSA-27jw-6xjf-hgxj","GHSA-853m-gvvm-6rvx"],"status":"published","title":"SiYuan before v3.8.0 Secret Exfiltration via http_request URL","description":"SiYuan before v3.8.0 interpolates secret placeholders into the destination URL parameter of the http_request MCP tool, allowing attackers to exfiltrate stored secrets. An MCP client can craft a request with an attacker-controlled URL containing secret placeholders to send plaintext secret values to any public host without confirmation.","severity":{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00413,"percentile":0.35918,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-201"],"published":"2026-08-22T12:26:35Z","modified":"2026-10-28T02:30:37Z","products":[{"vendor":"siyuan-note","product":"siyuan"}],"references":[{"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-853m-gvvm-6rvx","tags":["vendor-advisory","advisory"]},{"url":"https://www.vulncheck.com/advisories/siyuan-before-secret-exfiltration-via-http-request-url","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-59809","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-27jw-6xjf-hgxj"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59809.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-59809","title":"SiYuan before v3.8.0 Secret Exfiltration via http_request URL","description":"SiYuan before v3.8.0 interpolates secret placeholders into the destination URL parameter of the http_request MCP tool, allowing attackers to exfiltrate stored secrets. An MCP client can craft a request with an attacker-controlled URL containing secret placeholders to send plaintext secret values to any public host without confirmation.","status":"published","published":"2026-08-22T12:26:35.098Z","modified":"2026-08-26T16:16:52.009Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"},{"version":"3.1","score":4.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-201"],"updated_at":"2026-11-02T14:19:58.560602Z"}],"euvd":[{"id":"EUVD-2026-64267","description":"SiYuan before v3.8.0 interpolates secret placeholders into the destination URL parameter of the http_request MCP tool, allowing attackers to exfiltrate stored secrets. An MCP client can craft a request with an attacker-controlled URL containing secret placeholders to send plaintext secret values to any public host without confirmation.","status":"published","published":"2026-08-22T12:26:35Z","modified":"2026-08-26T16:16:52Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T18:01:30.542287Z"}],"ghsa":[{"id":"GHSA-27jw-6xjf-hgxj","title":"SiYuan before v3.8.0 interpolates secret placeholders into the destination URL parameter of the...","description":"SiYuan before v3.8.0 interpolates secret placeholders into the destination URL parameter of the http_request MCP tool, allowing attackers to exfiltrate stored secrets. An MCP client can craft a request with an attacker-controlled URL containing secret placeholders to send plaintext secret values to any public host without confirmation.","status":"published","published":"2026-08-22T15:31:02Z","modified":"2026-08-22T15:31:05Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"},{"version":"3.1","score":4.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"cwes":["CWE-201"],"updated_at":"2026-11-02T15:10:51.608425Z"}],"nvd":[{"id":"CVE-2026-59809","description":"SiYuan before v3.8.0 interpolates secret placeholders into the destination URL parameter of the http_request MCP tool, allowing attackers to exfiltrate stored secrets. An MCP client can craft a request with an attacker-controlled URL containing secret placeholders to send plaintext secret values to any public host without confirmation.","status":"published","published":"2026-08-22T13:16:39.127Z","modified":"2026-10-12T16:10:00.22Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"},{"version":"3.1","score":4.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-201"],"updated_at":"2026-11-02T14:12:40.665005Z"}],"osv":[{"id":"CVE-2026-59809","title":"SiYuan before v3.8.0 Secret Exfiltration via http_request URL","description":"SiYuan before v3.8.0 interpolates secret placeholders into the destination URL parameter of the http_request MCP tool, allowing attackers to exfiltrate stored secrets. An MCP client can craft a request with an attacker-controlled URL containing secret placeholders to send plaintext secret values to any public host without confirmation.","status":"published","published":"2026-08-22T12:26:35.098Z","modified":"2026-10-28T02:30:37.38161392Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-201"],"updated_at":"2026-11-02T15:45:12.496548Z"}]}}