Rule Category

FILE-OFFICE -- Snort detected traffic targeting vulnerabilities in files belonging to the Microsoft Office suite of software (Excel, PowerPoint, Word, Visio, Access, Outlook, etc.).

Alert Message

FILE-OFFICE Microsoft Office Equation Editor stack buffer overflow attempt

Rule Explanation

This rule detects the attempted download of an RTF file containing embedded Microsoft Equation Editor OLE data by searching for an object with the obfuscated class type of "Equation.3".

What To Look For

This rule detects the attempted download of an RTF file containing embedded Microsoft Equation Editor OLE data.

Known Usage

No public information

False Positives

No known false positives

Contributors

Cisco Talos Intelligence Group

MITRE ATT&CK Framework

Tactic: Execution

Technique: Exploitation for Client Execution

For reference, see the MITRE ATT&CK vulnerability types here: https://attack.mitre.org

CVE

Additional Links

Rule Vulnerability

Buffer Overflow

Buffer Overflows occur when a memory location is filled past its expected boundaries. Computer attackers target systems without proper terminating conditions on buffers, which then write the additional information in other locations in memory, overwriting what is there. This could corrupt the data, making the system behave erratically or crash. The new information could include malicious executable code, which might be executed.

CVE Additional Information

CVE-2017-11882
Microsoft Office 2007 Service Pack 3, Microsoft Office 2010 Service Pack 2, Microsoft Office 2013 Service Pack 1, and Microsoft Office 2016 allow an attacker to run arbitrary code in the context of the current user by failing to properly handle objects in memory, aka "Microsoft Office Memory Corruption Vulnerability". This CVE ID is unique from CVE-2017-11884.
Details
Severity Base Score7.8
Impact Score5.9 Exploit Score1.8
Confidentiality ImpactHIGH Integrity ImpactHIGH
Availability ImpactHIGH Access Vector
Authentication Ease of Access