{"id":"CVE-2026-82649","state":"PUBLISHED","title":"SiYuan before 3.8.1 Local Privilege Escalation via Uncontrolled Search Path","description":"SiYuan Windows installer before version 3.8.1 (affected versions >= 2.0.14) contains an uncontrolled search path element vulnerability in its NSIS installer, which invokes system executables such as TASKKILL by name rather than by absolute path. Because NSIS nsExec::Exec resolves these calls using a search path that includes the installer's own launch directory ahead of System32, an attacker who plants a malicious executable (e.g., a renamed TASKKILL.exe) in that directory can have it executed when the installer runs. These calls occur in electron-builder's preInit hook before the license page is displayed, and with an all-users (elevated) install the planted binary executes with an elevated token, resulting in local privilege escalation.","publishedAt":"2026-08-30T14:33:31.723Z","updatedAt":"2026-09-01T14:05:54.992Z","severity":{"score":7,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["siyuan-note siyuan"],"affected":[{"vendor":"siyuan-note","product":"siyuan","defaultStatus":"unaffected","versions":[{"version":"2.0.14","status":"affected","lessThan":"3.8.1","versionType":"semver"},{"version":"3.8.1","status":"unaffected","versionType":"semver"}]}],"references":["https://github.com/siyuan-note/siyuan/security/advisories/GHSA-9j65-967f-5rv3","https://github.com/siyuan-note/siyuan/commit/251596fc0de2f9528c00c224252fd073a99973f4","https://www.vulncheck.com/advisories/siyuan-before-3.8.1-local-privilege-escalation-via-uncontrolled-search-path"],"weaknesses":["CWE-427"],"ingestedAt":"2026-10-29T20:13:15.269Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/82xxx/CVE-2026-82649.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-82649","state":"PUBLISHED","datePublished":"2026-08-30T14:33:31.723Z","dateUpdated":"2026-09-01T14:05:54.992Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-08-30T13:38:00.101Z"},"containers":{"cna":{"title":"SiYuan before 3.8.1 Local Privilege Escalation via Uncontrolled Search Path","descriptions":[{"lang":"en","value":"SiYuan Windows installer before version 3.8.1 (affected versions >= 2.0.14) contains an uncontrolled search path element vulnerability in its NSIS installer, which invokes system executables such as TASKKILL by name rather than by absolute path. Because NSIS nsExec::Exec resolves these calls using a search path that includes the installer's own launch directory ahead of System32, an attacker who plants a malicious executable (e.g., a renamed TASKKILL.exe) in that directory can have it executed when the installer runs. These calls occur in electron-builder's preInit hook before the license page is displayed, and with an all-users (elevated) install the planted binary executes with an elevated token, resulting in local privilege escalation."}],"affected":[{"vendor":"siyuan-note","product":"siyuan","defaultStatus":"unaffected","versions":[{"version":"2.0.14","status":"affected","lessThan":"3.8.1","versionType":"semver"},{"version":"3.8.1","status":"unaffected","versionType":"semver"}]}],"references":[{"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-9j65-967f-5rv3","tags":["vendor-advisory"],"name":"GitHub Security Advisory (GHSA-9j65-967f-5rv3)"},{"url":"https://github.com/siyuan-note/siyuan/commit/251596fc0de2f9528c00c224252fd073a99973f4","tags":["patch"],"name":"Patch Commit"},{"url":"https://www.vulncheck.com/advisories/siyuan-before-3.8.1-local-privilege-escalation-via-uncontrolled-search-path","name":"VulnCheck Advisory: SiYuan before 3.8.1 Local Privilege Escalation via Uncontrolled Search Path","tags":["third-party-advisory"]}],"metrics":[{"format":"CVSS","cvssV4_0":{"version":"4.0","vectorString":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","attackVector":"LOCAL","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"LOW","userInteraction":"PASSIVE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":7,"baseSeverity":"HIGH"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-427","lang":"en","description":"Uncontrolled Search Path Element","type":"CWE"}]}],"providerMetadata":{"shortName":"VulnCheck","orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateUpdated":"2026-08-30T14:33:31.723Z"},"datePublic":"2026-08-16T00:00:00.000Z","cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*","versionStartIncluding":"2.0.14","versionEndExcluding":"3.8.1"}]}]}],"credits":[{"lang":"en","value":"pl4nty","type":"reporter"}],"x_generator":{"engine":"vulncheck-endgame"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-9j65-967f-5rv3","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-01T14:05:25.276556Z","id":"CVE-2026-82649","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-01T14:05:54.992Z"}}]}}}