An issue was discovered in Veritas Backup Exec before 21.2.

published 2021-03-01 5y ago modified 2026-06-17 4mo ago also EUVD-2021-14615

cvss: 8.2; version 3.1, CNA
cisa kev: Exploited; added 2023-04-07, used in ransomware
epss: 64.9%; EPSS 64.9% chance of exploitation in 30 days, percentile 99.2%
public exploits: 1; Metasploit, plus a Nuclei check

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.

Patch / fix

cisa required action Apply updates per vendor instructions.

fixed in 1

veritas backup_exec 21.2

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Timeline

2021-03-01 First public exploit (Metasploit exploit/multi/veritas/beagent_sha_auth_rce)
2021-03-01 Published
2023-04-07 Added to CISA KEV
2023-04-28 CISA patch deadline
2023-12-22 CISA SSVC: exploitation active

Known exploited

Added: 3y ago (2023-04-07)
Patch by: 2023-04-28 (3y ago)
Ransomware: Known to be used in ransomware campaigns
Required action: Apply updates per vendor instructions.
Vendor, product: Veritas, Backup Exec Agent
CISA name: Veritas Backup Exec Agent Improper Authentication Vulnerability

Ransomware

Groups reported to have exploited it in intrusions.

ALPHV ransomware gang

reported by cloud.google.com

Ransomware Vulnerability Matrix by BushidoUK (github.com/BushidoUK/Ransomware-Vulnerability-Matrix), reformatted per CVE. CC BY 4.0

CISA SSVC

Exploitation: Active, exploited in the wild
Automatable: yes
Technical impact: partial
Assessed: 2y ago (2023-12-22)

Exploit prediction

64.91% chance of exploitation in the next 30 days, higher than 99.2% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

Metasploit exploit/multi/veritas/beagent_sha_auth_rce Veritas Backup Exec Agent Remote Code Execution metasploit exploit, excellent rank, 2021-03-01
Nuclei template Veritas Backup Exec - Broken Authentication nuclei detection template
packetstormsecurity.com http://packetstormsecurity.com/files/168506/Veritas-Backup-Exec-Agent-Remote-Code-Execution.html referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.2	CVSS:3.1/AC:L/AV:N/A:N/C:H/I:L/PR:N/S:U/UI:N
CNA	3.1	8.2	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
NVD	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.5	AV:N/AC:L/Au:N/C:P/I:P/A:P

References

packetstormsecurity.com /files/168506/Veritas-Backup-Exec-Agent-Remote-Code-Execution.html
exploit, third-party-advisory, vdb-entry
veritas.com /content/support/en_US/security/VTS21-001#issue1
vendor-advisory
cisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27877
government-resource, us-government-resource

Sources

CVE List CVE-2021-27877
NVD CVE-2021-27877

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