{"id":"CVE-2021-26561","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-26561","generatedAt":"2026-10-27T21:20:38.901Z","title":"Stack-based buffer overflow vulnerability in synoagentregisterd in Synology DiskStation Manager (DSM) before 6.2.3-25426-3 allows man-in-the-middle attackers to execute arbitrary code via syno_finder_site HTTP header.","description":"Stack-based buffer overflow vulnerability in synoagentregisterd in Synology DiskStation Manager (DSM) before 6.2.3-25426-3 allows man-in-the-middle attackers to execute arbitrary code via syno_finder_site HTTP header.","published":"2021-02-26T22:15:20.000Z","lastModified":"2026-06-17T03:43:29.000Z","status":"Modified","sourceIdentifier":"security@synology.com","cvss":{"version":"3.1","score":8.1,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-121","CWE-119"],"affected":["synology/diskstation manager","synology/vs960hd firmware","synology/skynas firmware","synology/diskstation manager unified controller"],"epss":{"score":0.02061,"percentile":0.81201,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (2.06%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://www.synology.com/security/advisory/Synology_SA_20_26","tags":["Vendor Advisory"],"source":"security@synology.com"},{"url":"https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1159","tags":["Exploit","Third Party Advisory"],"source":"security@synology.com"},{"url":"https://www.synology.com/security/advisory/Synology_SA_20_26","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1159","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-26561","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}