CVE-2021-27876
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.
ACTIVELY EXPLOITED IN THE WILD
This vulnerability is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
Veritas Backup Exec Agent File Access Vulnerability
Veritas Backup Exec Agent
Apply updates per vendor instructions.
4/7/2023
https://www.veritas.com/support/en_US/security/VTS21-001; https://nvd.nist.gov/vuln/detail/CVE-2021-27876
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
CVSS v2 Score
AV:N/AC:L/Au:S/C:C/I:P/A:N
EPSS Score (Exploitation Probability)
This vulnerability has a 0.91% probability of being exploited in the next 30 days, ranking higher than 76% of all scored CVEs.
CWE Classification
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Similar SeverityHIGH
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