{"id":"CVE-2021-27877","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-27877","generatedAt":"2026-10-31T15:10:20.750Z","title":"Veritas Backup Exec Agent Improper Authentication Vulnerability","description":"An issue was discovered in Veritas Backup Exec before 21.2. It supports multiple authentication schemes: SHA authentication is one of these. This authentication scheme is no longer used in current versions of the product, but hadn't yet been disabled. An attacker could remotely exploit this scheme to gain unauthorized access to an Agent and execute privileged commands.","published":"2021-03-01T22:15:14.000Z","lastModified":"2026-06-17T03:45:33.000Z","status":"Analyzed","sourceIdentifier":"cve@mitre.org","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":[],"affected":["veritas/backup exec"],"epss":{"score":0.6491,"percentile":0.99246,"date":"2026-10-30","history":[]},"kev":{"listed":true,"dateAdded":"2023-04-07","dueDate":"2023-04-28","knownRansomwareCampaignUse":"Known","notes":"Apply updates per vendor instructions.\nhttps://www.veritas.com/support/en_US/security/VTS21-001; https://nvd.nist.gov/vuln/detail/CVE-2021-27877"},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"Known to be exploited in the wild (CISA KEV, CISA remediation deadline 28 April 2023). Treat as an emergency change: patch or isolate now, then hunt for prior compromise."},"changes":[],"references":[{"url":"http://packetstormsecurity.com/files/168506/Veritas-Backup-Exec-Agent-Remote-Code-Execution.html","tags":["Exploit","Third Party Advisory","VDB Entry"],"source":"cve@mitre.org"},{"url":"https://www.veritas.com/content/support/en_US/security/VTS21-001#issue1","tags":["Vendor Advisory"],"source":"cve@mitre.org"},{"url":"http://packetstormsecurity.com/files/168506/Veritas-Backup-Exec-Agent-Remote-Code-Execution.html","tags":["Exploit","Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.veritas.com/content/support/en_US/security/VTS21-001#issue1","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27877","tags":["US Government Resource"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-27877","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."}