{"id":"CVE-2021-34346","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-34346","generatedAt":"2026-10-27T22:32:05.124Z","title":"A stack buffer overflow vulnerability has been reported to affect QNAP device running NVR Storage Expansion.","description":"A stack buffer overflow vulnerability has been reported to affect QNAP device running NVR Storage Expansion. If exploited, this vulnerability allows attackers to execute arbitrary code. We have already fixed this vulnerability in the following versions of NVR Storage Expansion: NVR Storage Expansion 1.0.6 ( 2021/08/03 ) and later","published":"2021-09-10T04:15:19.000Z","lastModified":"2026-06-17T03:55:42.000Z","status":"Modified","sourceIdentifier":"security@qnapsecurity.com.tw","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-787"],"affected":["qnap/nvr storage expansion firmware"],"epss":{"score":0.01579,"percentile":0.75325,"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 (1.58%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://www.qnap.com/en/security-advisory/qsa-21-36","tags":["Vendor Advisory"],"source":"security@qnapsecurity.com.tw"},{"url":"https://www.qnap.com/en/security-advisory/qsa-21-36","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-34346","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."}