CVE Identifier(s): CVE-2018-18331, CVE-2018-18332
CVSS 3.0 Score(s): 5.9
Severity Rating(s): Medium
Trend Micro has released a new Critical Patch (CP) for Trend Micro OfficeScan XG. This CP resolves two vulnerabilities related to weak file permissions.
Trend Micro has released the following solutions to address the issue. Please note there is an additional step below to complete the necessary configuration:
This is the minimum version(s) of the patch and/or build required to address the issue. Trend Micro highly encourages customers to obtain the latest version of the product if there is a newer one available than the one listed in this bulletin.
Customers are encouraged to visit Trend Micro’s Download Center to obtain prerequisite software (such as Service Packs) before applying any of the solutions above.
Adding and Deploying the "PrivilegeContolSetting" in OfficeScan
This update resolves two vulnerabilities in Trend Micro OfficeScan XG:
1. CVE-2018-18331: Weak file permissions on a particular folder for a particular group may allow an attacker to alter the files, which could lead to other exploits.
2. CVE-2018-18332: Permissions on some key files can be potentially manipulated to modify other files and folders.
In addition to the two vulnerabilities discovered and addressed above, another potential issue was reported and is being given a Defense in Depth (DiD) credit:
3. *Defense in Depth (DiD) Credit: An attacker may attempt shutdown Trend Micro OfficeScan services or prevent them from running on startup using a specially crafted file on Windows 10. However, the attacker must already have obtained administrator privileges beforehand either legitimately or via a entirely different exploit. Please see the mitigating factors below for this issue since it is not completely addressed in the CP above.
Due to the seriousness of these vulnerabilities, customers are highly encouraged to update to the latest build as soon as possible.
Exploiting these type of vulnerabilities generally require that an attacker has access (physical or remote) to a vulnerable machine. In addition to timely application of patches and updated solutions, customers are also advised to review remote access to critical systems and ensure policies and perimeter security is up-to-date.
* For the DiD Credit mentioned above, the current mitigation strategy is to ensure that administrator access on client machines are sufficently secured to legitmate users only to prevent such a scenario from happening. A malicious user with administrator or root level access on a client machine is capable of doing serious damage to the operating system itself and is not limited to applications - including OfficeScan. The OfficeScan product development team is currently evaluating how to better protect against an attack such as this while still respsecting the operating system privileges intended by the OS vendor.
However, even though an exploit may require several specific conditions to be met, Trend Micro strongly encourages customers to update to the latest builds as soon as possible.
Trend Micro would like to thank the following individuals for responsibly disclosing these issues and working with Trend Micro to help protect our customers:
- Abdullah H. AlJaber (@al_jaber) - http://AJ.SA