Vulnerabilities > CVE-2020-36167 - Unrestricted Upload of File with Dangerous Type vulnerability in Veritas Backup Exec 20.0/21.0

047910
CVSS 7.2 - HIGH
Attack vector
LOCAL
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
COMPLETE
Integrity impact
COMPLETE
Availability impact
COMPLETE
local
low complexity
veritas
CWE-434

Summary

An issue was discovered in the server in Veritas Backup Exec through 16.2, 20.6 before hotfix 298543, and 21.1 before hotfix 657517. On start-up, it loads the OpenSSL library from the Installation folder. This library in turn attempts to load the /usr/local/ssl/openssl.cnf configuration file, which may not exist. On Windows systems, this path could translate to <drive>:\usr\local\ssl\openssl.cnf. A low privileged user can create a :\usr\local\ssl\openssl.cnf configuration file to load a malicious OpenSSL engine, resulting in arbitrary code execution as SYSTEM when the service starts. This gives the attacker administrator access on the system, allowing the attacker (by default) to access all data, access all installed applications, etc. If the system is also an Active Directory domain controller, then this can affect the entire domain.

Vulnerable Configurations

Part Description Count
Application
Veritas
2

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Accessing Functionality Not Properly Constrained by ACLs
    In applications, particularly web applications, access to functionality is mitigated by the authorization framework, whose job it is to map ACLs to elements of the application's functionality; particularly URL's for web apps. In the case that the administrator failed to specify an ACL for a particular element, an attacker may be able to access it with impunity. An attacker with the ability to access functionality not properly constrained by ACLs can obtain sensitive information and possibly compromise the entire application. Such an attacker can access resources that must be available only to users at a higher privilege level, can access management sections of the application or can run queries for data that he is otherwise not supposed to.
  • Privilege Abuse
    An adversary is able to exploit features of the target that should be reserved for privileged users or administrators but are exposed to use by lower or non-privileged accounts. Access to sensitive information and functionality must be controlled to ensure that only authorized users are able to access these resources. If access control mechanisms are absent or misconfigured, a user may be able to access resources that are intended only for higher level users. An adversary may be able to exploit this to utilize a less trusted account to gain information and perform activities reserved for more trusted accounts. This attack differs from privilege escalation and other privilege stealing attacks in that the adversary never actually escalates their privileges but instead is able to use a lesser degree of privilege to access resources that should be (but are not) reserved for higher privilege accounts. Likewise, the adversary does not exploit trust or subvert systems - all control functionality is working as configured but the configuration does not adequately protect sensitive resources at an appropriate level.