CVE-2021-27876 on CISA KEV

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 attac

01What CISA says about this vulnerability

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…

02Required action — verbatim from CISA

Apply updates per vendor instructions.

03Notes & references

• www.veritas.com — https://www.veritas.com/content/support/en_US/security/VTS21-001#issue2
• packetstormsecurity.com — http://packetstormsecurity.com/files/168506/Veritas-Backup-Exec-Agent-Remote-Cod…

04SARA's analyst layer — why this matters

This vulnerability is currently on the CISA KEV list, which CISA only adds CVEs to when there is reliable evidence of active exploitation in the wild. For federal civilian agencies, BOD 22-01 requires remediation by the due date above. For everyone else, KEV is the strongest "patch immediately" signal you can get from public threat intel.

05Affected products (summary)

Vendor	Product	Versions
n	a / n/a	n/a

06Detection

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