CVE-2021-27877
KEV RANSOMWARECRITICAL 9.8EPSS 64.9%
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.
- CVSS v3.1
- 9.8 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS v3.1
- 8.2 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N - CVSS v2.0
- 7.5 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P - EPSS
- 64.91% chance of exploitation in the next 30 days, 99th percentile
- CISA KEV
- added 2023-04-07, used in ransomware campaigns
- Nuclei
- high
- Published
- 2021-03-01
- Updated
- 2025-10-21
Proof-of-concept exploits (2)
- http://packetstormsecurity.com/files/168506/Veritas-Backup-Exec-Agent-Remote-Code-Executi…
- yashswarup12/CVE-2021-27877-PoC