A Vulnerability in Clam AntiVirus Could Allow for Remote Code Execution

ITS ADVISORY NUMBER:
2023-020

DATE(S) ISSUED:
02/17/2023

SUBJECT:
A Vulnerability in Clam AntiVirus Could Allow for Remote Code Execution

OVERVIEW:
A vulnerability has been discovered in Clam AntiVirus, which could allow for remote code execution. Clam AntiVirus is an open-source, cross-platform antimalware toolkit able to detect many types of malware. Successful exploitation of this vulnerability could allow an attacker to execute remote code as the Clam AntiVirus platform. Depending on the privileges associated with the application, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Applications that are configured to have fewer user rights on the system could be less impacted than those that operate with administrative user rights.

THREAT INTELLIGENCE:
There are currently no reports of this vulnerability being exploited in the wild.

SYSTEMS AFFECTED:

  • Clam AntiVirus 0.103.8 and prior
  • Clam AntiVirus 0.105.2 and prior
  • Clam AntiVirus 1.0.1 and prior
  • Secure Endpoint, formerly Advanced Malware Protection (AMP) for Endpoints, for Linux versions prior to 1.20.2
  • Secure Endpoint, formerly Advanced Malware Protection (AMP) for Endpoints, for MacOS versions prior to 1.21.1
  • Secure Endpoint, formerly Advanced Malware Protection (AMP) for Endpoints, for Windows versions prior to 7.5.9 and 8.1.5
  • Secure Endpoint Private Cloud versions prior 3.6.0 or later with updated connectors
  • Secure Web Appliance, formerly Web Security Appliance    versions prior to 14.0.4-005 and 15.0.0.0-254

 

RISK:
Government:

  • Large and medium government entities: Medium
  • Small government entities: Medium

 

Businesses:

  • Large and medium business entities: Medium
  • Small business entities: Medium

Home users: Low

TECHNICAL SUMMARY:
A vulnerability has been discovered in Clam AntiVirus, which could allow for remote code execution. Details of this vulnerability are as follows: 

Tactic: Execution (TA0002):
            Technique: Exploitation for Client Execution (T1203):

  • CVE-2023-20032 – A vulnerability in the HFS+ partition file parser of Clam AntiVirus  versions 1.0.0 and earlier, 0.105.1 and earlier, and 0.103.7 and earlier could allow an unauthenticated, remote attacker to execute arbitrary code. This vulnerability is due to a missing buffer size check that may result in a heap buffer overflow write. An attacker could exploit this vulnerability by submitting a crafted HFS+ partition file to be scanned by Clam AntiVirus on an affected device. A successful exploit could allow the attacker to execute arbitrary code with the privileges of the Clam AntiVirus scanning process, or else crash the process, resulting in a denial of service (DoS) condition.

Successful exploitation of this vulnerability could allow an attacker to execute remote code as the Clam AntiVirus platform. Depending on the privileges associated with the application, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Applications that are configured to have fewer user rights on the system could be less impacted than those that operate with administrative user rights.

RECOMMENDATIONS:
We recommend the following actions be taken:

  • Apply the stable channel update provided by Cisco to vulnerable systems immediately after appropriate testing. (M1051: Update Software)
    • Safeguard 7.1 : Establish and Maintain a Vulnerability Management Process: Establish and maintain a documented vulnerability management process for enterprise assets. Review and update documentation annually, or when significant enterprise changes occur that could impact this Safeguard.
    • Safeguard 7.4: Perform Automated Application Patch Management: Perform application updates on enterprise assets through automated patch management on a monthly, or more frequent, basis.
    • Safeguard 7.5 : Perform Automated Vulnerability Scans of Internal Enterprise Assets: Perform automated vulnerability scans of internal enterprise assets on a quarterly, or more frequent, basis. Conduct both authenticated and unauthenticated scans, using a SCAP-compliant vulnerability scanning tool.
  • Apply the Principle of Least Privilege to all systems and services. Run all software as a non-privileged user (one without administrative privileges) to diminish the effects of a successful attack. (M1026: Privileged Account Management)
    • Safeguard 4.7: Manage Default Accounts on Enterprise Assets and Software: Manage default accounts on enterprise assets and software, such as root, administrator, and other pre-configured vendor accounts. Example implementations can include: disabling default accounts or making them unusable.
    • Safeguard 5.4: Restrict Administrator Privileges to Dedicated Administrator Accounts: Restrict administrator privileges to dedicated administrator accounts on enterprise assets. Conduct general computing activities, such as internet browsing, email, and productivity suite use, from the user’s primary, non-privileged account.
  • Use capabilities to detect and block conditions that may lead to or be indicative of a software exploit occurring. (M1050: Exploit Protection)
    • Safeguard 10.5:  Enable Anti-Exploitation Features: Enable anti-exploitation features on enterprise assets and software, where possible, such as Microsoft® Data Execution Prevention (DEP), Windows® Defender Exploit Guard (WDEG), or Apple® System Integrity Protection (SIP) and Gatekeeper™.
  • Restrict use of certain websites, block downloads/attachments, block Javascript, restrict browser extensions, etc. (M1021: Restrict Web-Based Content)
    • Safeguard 9.2: Use DNS Filtering Services: Use DNS filtering services on all enterprise assets to block access to known malicious domains.
    • Safeguard 9.3: Maintain and Enforce Network-Based URL Filters: Enforce and update network-based URL filters to limit an enterprise asset from connecting to potentially malicious or unapproved websites. Example implementations include category-based filtering, reputation-based filtering, or through the use of block lists. Enforce filters for all enterprise assets.
    • Safeguard 9.6: Block Unnecessary File Types: Block unnecessary file types attempting to enter the enterprise’s email gateway.
  • Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources. Inform and educate users regarding the threats posed by hypertext links contained in emails or attachments especially from un-trusted sources. (M1017: User Training)
    • Safeguard 14.1: Establish and Maintain a Security Awareness Program: Establish and maintain a security awareness program. The purpose of a security awareness program is to educate the enterprise’s workforce on how to interact with enterprise assets and data in a secure manner. Conduct training at hire and, at a minimum, annually. Review and update content annually, or when significant enterprise changes occur that could impact this Safeguard.

Safeguard 14.2: Train Workforce Members to Recognize Social Engineering Attacks: Train workforce members to recognize social engineering attacks, such as phishing, pre-texting, and tailgating.

REFERENCES:

Clam AntiVirus:

https://blog.clamav.net/

Cisco:

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-clamav-q8DThCy

CVE:

https://cve.mitre.org/cgi-bin/cvename.cgi?name= CVE-2023-20032