Zero-day vulnerability in Microsoft .NET Framework

Improper input validation
CVE-2017-8759

The vulnerability was detected by FireEye  researchers. The attacker used Microsoft Office RTF document to leverage RCE in .NET Framework and deploy FINSPY malware. The malicious document “Проект.doc” (MD5: fe5c4d6bb78e170abf5cf3741868ea4c) had Russian name and might have been used to target a Russian speaker.

Known malware:

FINSPY

Vulnerability details

Advisory: SB2017091210 - Remote code execution in Microsoft .NET Framework

Vulnerable component: Microsoft .NET Framework

CVE-ID: CVE-2017-8759

CVSSv3 score: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:H/RL:O/RC:C

CWE-ID: CWE-20 - Improper Input Validation

Description:

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to uncpecified error when processing untrusted input. A remote unauthenticated attacker can execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Note: this vulnerability is being actively exploited in the wild.

Public Exploits:

Latest references in media:

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