עברית

Vulnerability Intelligence

CVE-2021-27876

High 8.1 Exploited in the wild (KEV) Used in ransomware campaigns

Published
Last modified
NVD status
Analyzed

CISA KEV catalog

Confirmed active exploitation.

Listed in CISA's catalog of Known Exploited Vulnerabilities: attackers are using it in real attacks. Patch it with priority.

CISA KEV
Name
Veritas Backup Exec Agent File Access Vulnerability
Added to catalog
Remediation due date (US federal)
Required action
Apply updates per vendor instructions.

Description

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.

Affected products

veritas: backup exec

References5

Metrics

CVSS 3.1
8.1 HIGH Score source: NVD CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
EPSS — exploit probability
14% percentile: 96 · as of 2 November 2026

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