Microsoft’s Patch Tuesday updates for September 2017 address roughly 80 vulnerabilities, including a zero-day exploited by threat actors to deliver spyware and several flaws that have been publicly disclosed.
The vulnerability exploited in attacks, reported to Microsoft by researchers at FireEye, is tracked as CVE-2017-8759 and it affects the .NET framework. The attacks have been linked by Microsoft to a threat group identified as NEODYMIUM.
In the attacks observed by FireEye, hackers exploited CVE-2017-8759 via specially crafted documents to deliver FinFisher (FinSpy/WingBird) malware to Russian-speaking users. Despite being actively exploited, Microsoft has assigned an “important” severity rating to this vulnerability.
Microsoft’s latest security updates also fix three issues that were publicly disclosed before the patches were made available. This includes a moderate severity security feature bypass bug in Edge (CVE-2017-8723) that the company believes is unlikely to be exploited.
Another publicly disclosed security bypass flaw affects the Device Guard feature and it allows an attacker to inject malicious code into a Windows PowerShell session. A vulnerability in Broadcom chipsets that exposes Hololens to remote code execution has also been disclosed.
“The three public disclosures this month are all on the Windows 10 platform. Two in the OS and one in the Edge browser. While all three of these have lower exploitability index ratings, the fact that they have been Publicly Disclosed means a threat actor has enough information to potentially create an exploit,” said Chris Goettl, product manager at Ivanti. “Public Disclosures are a threat indicator to watch for as they are at higher risk of being exploited since some of the busy work of research and finding how to exploit may have been done for them already.”
Microsoft has patched tens of critical vulnerabilities in Internet Explorer, Edge, Windows, and NetBIOS. Important flaws have been addressed in web browsers, Hyper-V, Exchange, Windows, Office, and SharePoint.
The company has also released an advisory for a patch that addresses a Bluetooth driver spoofing vulnerability disclosed by IoT security firm Armis on Tuesday. The flaw, which makes BlueBorne attacks possible, was patched by the company in July, but disclosure was withheld until other vendors could develop and release fixes.
Adobe also released security updates on Tuesday. The company patched only two vulnerabilities in Flash Player this month, but both have been classified as critical and they both allow remote code execution.