CVE-2017-6401 in NetBackup
Summary
by MITRE
An issue was discovered in Veritas NetBackup before 8.0 and NetBackup Appliance before 3.0. Local arbitrary command execution can occur when using bpcd and bpnbat.
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Analysis
by VulDB Data Team • 09/02/2020
The vulnerability identified as CVE-2017-6401 represents a critical local arbitrary command execution flaw affecting Veritas NetBackup and NetBackup Appliance products. This security weakness exists within the bpcd and bpnbat components, which are fundamental elements of the NetBackup architecture responsible for backup operations and communication protocols. The vulnerability stems from insufficient input validation and improper privilege handling within these services, creating an exploitable condition that allows local attackers to execute arbitrary commands with elevated privileges. The flaw particularly affects versions prior to NetBackup 8.0 and NetBackup Appliance 3.0, indicating a long-standing issue that was not adequately addressed in the affected product lines.
The technical implementation of this vulnerability involves the manipulation of command-line arguments or input parameters passed to the bpcd and bpnbat processes. When these services process user-supplied data without proper sanitization, they become susceptible to command injection attacks. Attackers can leverage this weakness by crafting malicious input that gets executed within the context of the privileged processes. The bpcd service typically operates with elevated privileges to manage backup operations, while bpnbat handles batch processing tasks, making both components prime targets for exploitation. This vulnerability aligns with CWE-78, which describes improper neutralization of special elements used in OS commands, and represents a classic command injection flaw that can be exploited to gain unauthorized system access.
The operational impact of CVE-2017-6401 extends beyond simple privilege escalation, as it provides attackers with the ability to execute arbitrary code on affected systems. This capability enables comprehensive system compromise including data exfiltration, installation of persistent backdoors, modification of backup configurations, and potential lateral movement within network environments. Organizations utilizing affected NetBackup versions face significant risk of unauthorized access to critical backup infrastructure, potentially leading to complete system compromise and data loss. The vulnerability particularly affects enterprise environments where NetBackup systems are deployed to manage large-scale backup operations, making it attractive to threat actors targeting critical infrastructure. This flaw also aligns with ATT&CK technique T1059, which covers command and scripting interpreter, and T1068, involving exploit for privilege escalation.
Mitigation strategies for CVE-2017-6401 primarily focus on upgrading to supported versions of Veritas NetBackup and NetBackup Appliance where the vulnerability has been addressed. Organizations should prioritize immediate patch deployment to versions 8.0 and 3.0 respectively, as these releases contain the necessary security fixes. Additionally, implementing network segmentation and access controls can limit the attack surface by restricting local access to affected systems. Security monitoring should be enhanced to detect suspicious command execution patterns and unauthorized access attempts. System hardening measures including disabling unnecessary services, implementing proper user privilege controls, and regular security audits can further reduce the risk of exploitation. Organizations should also consider implementing application whitelisting policies to prevent execution of unauthorized binaries that could be used in exploitation attempts. The vulnerability demonstrates the importance of maintaining current security patches and implementing defense-in-depth strategies to protect critical backup infrastructure from sophisticated attacks.