CVE-2021-27878
Veritas Backup Exec Agent Command Execution
- Published1 Mar 2021
- Added to CISA KEV7 Apr 2023
- Remediation due28 Apr 2023
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. The attacker could use one of these commands to execute an arbitrary command on the system using system privileges.
CVSS 3.1 breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HAffected products
Remediation
References
Frequently asked
Is CVE-2021-27878 being actively exploited?
Yes. CVE-2021-27878 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 7 Apr 2023. It has been used in ransomware campaigns.
How severe is CVE-2021-27878?
CVE-2021-27878 has a CVSS 3.1 base score of 8.8, rated high. EPSS estimates a 24.0% probability of exploitation.
Which products are affected by CVE-2021-27878?
Affected products include Veritas Backup Exec.
How do I fix CVE-2021-27878?
Upgrade affected software to a fixed version, for example Veritas Backup Exec 21.2 or later, then confirm no affected versions remain in your inventory.
How Secuno handles this
Secuno correlates vulnerabilities like CVE-2021-27878 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, Secuno flags any affected asset as top-priority automatically. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.
Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.