{"id":"CVE-2026-85581","aliases":["EUVD-2026-71004","GHSA-4qv4-f447-c9m2","GHSA-wv96-wmf5-xvj2"],"status":"published","title":"SiYuan before v3.8.2 Denial of Service via unauthenticated UI-process registration","description":"SiYuan before v3.8.2 contains a denial of service vulnerability in the unauthenticated /api/system/uiproc endpoint that accepts and retains attacker-controlled process identifiers without size limits or authentication. Attackers can send repeated requests with unique identifiers to exhaust process memory and degrade service availability.","severity":{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00575,"percentile":0.47884,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-770"],"published":"2026-09-04T11:29:50Z","modified":"2026-10-28T02:30:22Z","products":[{"vendor":"siyuan-note","product":"siyuan"}],"references":[{"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-wv96-wmf5-xvj2","tags":["vendor-advisory","advisory"]},{"url":"https://www.vulncheck.com/advisories/siyuan-before-3.8.2-denial-of-service-via-unauthenticated-ui-process-registration","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-85581","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-4qv4-f447-c9m2"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/85xxx/CVE-2026-85581.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-85581","title":"SiYuan before v3.8.2 Denial of Service via unauthenticated UI-process registration","description":"SiYuan before v3.8.2 contains a denial of service vulnerability in the unauthenticated /api/system/uiproc endpoint that accepts and retains attacker-controlled process identifiers without size limits or authentication. Attackers can send repeated requests with unique identifiers to exhaust process memory and degrade service availability.","status":"published","published":"2026-09-04T11:29:50.151Z","modified":"2026-09-10T15:09:54.88Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:19:52.773089Z"}],"euvd":[{"id":"EUVD-2026-71004","description":"SiYuan before v3.8.2 contains a denial of service vulnerability in the unauthenticated /api/system/uiproc endpoint that accepts and retains attacker-controlled process identifiers without size limits or authentication. Attackers can send repeated requests with unique identifiers to exhaust process memory and degrade service availability.","status":"published","published":"2026-09-04T11:29:50Z","modified":"2026-09-10T15:09:54Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T17:28:24.501469Z"}],"ghsa":[{"id":"GHSA-4qv4-f447-c9m2","title":"SiYuan before v3.8.2 contains a denial of service vulnerability in the unauthenticated /api...","description":"SiYuan before v3.8.2 contains a denial of service vulnerability in the unauthenticated /api/system/uiproc endpoint that accepts and retains attacker-controlled process identifiers without size limits or authentication. Attackers can send repeated requests with unique identifiers to exhaust process memory and degrade service availability.","status":"published","published":"2026-09-04T12:30:58Z","modified":"2026-09-04T12:30:58Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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":"high"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T15:11:21.957806Z"}],"nvd":[{"id":"CVE-2026-85581","description":"SiYuan before v3.8.2 contains a denial of service vulnerability in the unauthenticated /api/system/uiproc endpoint that accepts and retains attacker-controlled process identifiers without size limits or authentication. Attackers can send repeated requests with unique identifiers to exhaust process memory and degrade service availability.","status":"published","published":"2026-09-04T12:17:20.05Z","modified":"2026-09-10T16:17:59.087Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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":"high","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:12:43.737972Z"}],"osv":[{"id":"CVE-2026-85581","title":"SiYuan before v3.8.2 Denial of Service via unauthenticated UI-process registration","description":"SiYuan before v3.8.2 contains a denial of service vulnerability in the unauthenticated /api/system/uiproc endpoint that accepts and retains attacker-controlled process identifiers without size limits or authentication. Attackers can send repeated requests with unique identifiers to exhaust process memory and degrade service availability.","status":"published","published":"2026-09-04T11:29:50.151Z","modified":"2026-10-28T02:30:22.253477649Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T15:45:18.825071Z"}]}}