Rule Category

BROWSER-IE -- Snort has detected traffic known to exploit vulnerabilities present in the Internet Explorer browser, or products that have the Trident or Tasman engines.

Alert Message

BROWSER-IE Microsoft Edge JIT floating point value type confusion attempt

Rule Explanation

This event is generated when an html file containing malicious values traverses the corporate network. Impact: Attempted User Privilege Gain Details: A type confusion vulnerability has been identified in Windows Edge, that could allow an attacker to execute arbitrary code on the targeted host. The bug specifically occurs in the way the JIT(Just-In-Time) engine for Edge browser handles float values. In certain specific conditions , the dynamically generated JIT code fails to keep track of the type of an object when handling type conversions resulting from assigning float values to this object. This is a type confusion in chakra engine due to insufficient check when setting a float value to var array. Ease of Attack:

What To Look For

Known Usage

No public information

False Positives

No known false positives

Contributors

Cisco Talos Intelligence Group

MITRE ATT&CK Framework

Tactic:

Technique:

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

CVE

Additional Links

CVE Additional Information

CVE-2018-8555
A remote code execution vulnerability exists in the way that the Chakra scripting engine handles objects in memory in Microsoft Edge, aka "Chakra Scripting Engine Memory Corruption Vulnerability." This affects Microsoft Edge, ChakraCore. This CVE ID is unique from CVE-2018-8541, CVE-2018-8542, CVE-2018-8543, CVE-2018-8551, CVE-2018-8556, CVE-2018-8557, CVE-2018-8588.
Details
Severity Base Score7.5
Impact Score5.9 Exploit Score1.6
Confidentiality ImpactHIGH Integrity ImpactHIGH
Availability ImpactHIGH Access Vector
Authentication Ease of Access