CVE-2021-27876 (GCVE-0-2021-27876)
Vulnerability from cvelistv5
Published
2021-03-01 21:49
Modified
2025-07-30 01:38
Severity ?
8.1 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
CWE
  • n/a
Summary
An issue was discovered in Veritas Backup Exec before 21.2. The communication between a client and an Agent requires successful authentication, which is typically completed over a secure TLS communication. However, due to a vulnerability in the SHA Authentication scheme, an attacker is able to gain unauthorized access and complete the authentication process. Subsequently, the client can execute data management protocol commands on the authenticated connection. By using crafted input parameters in one of these commands, an attacker can access an arbitrary file on the system using System privileges.
References
cve@mitre.orghttp://packetstormsecurity.com/files/168506/Veritas-Backup-Exec-Agent-Remote-Code-Execution.htmlExploit, Third Party Advisory, VDB Entry
cve@mitre.orghttps://www.veritas.com/content/support/en_US/security/VTS21-001#issue2Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108http://packetstormsecurity.com/files/168506/Veritas-Backup-Exec-Agent-Remote-Code-Execution.htmlExploit, Third Party Advisory, VDB Entry
af854a3a-2127-422b-91ae-364da2661108https://www.veritas.com/content/support/en_US/security/VTS21-001#issue2Vendor Advisory
Impacted products
Vendor Product Version
n/a n/a Version: n/a
CISA Known exploited vulnerability
Data from the Known Exploited Vulnerabilities Catalog

Date added: 2023-04-07

Due date: 2023-04-28

Required action: Apply updates per vendor instructions.

Used in ransomware: Known

Notes: https://www.veritas.com/support/en_US/security/VTS21-001; https://nvd.nist.gov/vuln/detail/CVE-2021-27876

Show details on NVD website

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