CVE & CISA-KEV Catalog

CVE-2021-27876

HIGHCISA KEVEPSS 96th pctl
8.1
CVSS v3
NVD

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.

CVSS v3 Vector

Exploitability

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeUnchanged

Impact

ConfidentialityHigh
IntegrityHigh
AvailabilityNone

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Exploit Intelligence

13.41%probability of exploitation in 30 days
96thpercentile

Very high risk: more likely to be exploited than 96% of all known CVEs.

Known Exploited Vulnerability (CISA KEV)

Veritas Backup Exec Agent File Access Vulnerability

Veritas Backup Exec (BE) Agent contains a file access vulnerability that could allow an attacker to specially craft input parameters on a data management protocol command to access files on the BE Agent machine.

Apply updates per vendor instructions.

Remediation due: 2023-04-28

Associated with ransomware campaigns

References

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2025-11-03.