Source: cve@mitre.org
BackWeb client stores the username and password in cleartext for proxy authentication in the Communication registry key, which could allow other local users to gain privileges by reading the password.
BackWeb client versions are vulnerable to a local privilege escalation attack. This vulnerability allows an attacker to retrieve stored cleartext credentials for proxy authentication, enabling unauthorized access to network resources and potentially compromising the entire system. This is a critical security flaw that can be exploited by any local user with access to the registry.
Step 1: Target Identification: The attacker identifies a system running a vulnerable version of the BackWeb client.
Step 2: Registry Access: The attacker gains local access to the target system, either through physical access, social engineering, or exploiting another vulnerability.
Step 3: Registry Key Location: The attacker identifies the Communication registry key where the BackWeb client stores its proxy authentication credentials.
Step 4: Credential Retrieval: The attacker reads the username and password stored in cleartext from the Communication registry key.
Step 5: Credential Use: The attacker uses the retrieved username and password to authenticate to the proxy server, gaining unauthorized access to network resources, potentially leading to further compromise.
The vulnerability stems from the BackWeb client's insecure storage of proxy authentication credentials. Specifically, the client stores the username and password in cleartext within the Windows registry under the Communication key. This lack of encryption or secure storage mechanisms allows any local user with read access to the registry to easily retrieve these credentials. The root cause is a failure to implement secure credential management practices, such as encrypting the credentials using a strong algorithm or utilizing the Windows Credential Manager. The design flaw directly exposes sensitive information, making it trivial for an attacker to gain unauthorized access.
This vulnerability is not directly associated with specific APT groups due to its age and simplicity. However, it could be leveraged by any attacker seeking to escalate privileges on a compromised system. The ease of exploitation makes it a low-hanging fruit for opportunistic attackers. CISA KEV: Not Listed
Monitor the Windows registry for suspicious access to the Communication key within the BackWeb client's registry path.
Analyze process creation and command-line arguments for evidence of registry key access tools (e.g., reg.exe, powershell.exe).
Review security event logs for user activity related to registry modification or access, especially involving the BackWeb client's registry entries.
Use file integrity monitoring tools to detect changes to the BackWeb client's configuration files or registry keys.
Network traffic analysis to detect proxy authentication attempts using credentials that are not authorized.
Uninstall the BackWeb client if it's no longer required. This is the most effective remediation.
If the BackWeb client is necessary, upgrade to the latest version, if available, to mitigate the vulnerability. Check for vendor patches.
Implement a Group Policy to restrict access to the registry keys used by the BackWeb client for all users except those requiring it.
Implement strong password policies and multi-factor authentication for all user accounts.
Use a security information and event management (SIEM) system to monitor for suspicious activity related to registry access and credential usage.
Conduct regular vulnerability scans to identify and address security weaknesses in the environment.
If the client cannot be updated or removed, consider using a proxy server that supports authentication with more secure methods, such as Kerberos or NTLM, and configure the BackWeb client to use those methods if possible.