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# Palo Alto Networks

## zero-days

[![How Quickly Are We Patching Microsoft Exchange Servers?](https://www2.paloaltonetworks.com/blog/wp-content/uploads/2021/03/Pen-Pointing.jpg)](https://www2.paloaltonetworks.com/blog/2021/03/patching-microsoft-exchange-servers/)  
[How Quickly Are We Patching Microsoft Exchange Servers?
\-------------------------------------------------------](https://www2.paloaltonetworks.com/blog/2021/03/patching-microsoft-exchange-servers/)

Telemetry data from Expanse's attack surface management platform details how quickly organizations are patching Microsoft Exchange Servers.  
[Must-Read Articles](https://www.paloaltonetworks.com/blog/security-operations/category/must-read-articles/?ts=markdown)  
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Mar 14, 2021  
By [Matt Kraning](https://www.paloaltonetworks.com/blog/author/matt-kraning/?ts=markdown "Posts by Matt Kraning")

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![What Are Unknown Cyber Threats? (And Are They Really Unknown?)](https://www2.paloaltonetworks.com/blog/wp-content/uploads/2016/11/blog-generic-banner-1.jpg)  
[Security Platform](https://www.paloaltonetworks.com/blog/category/security-platform/?ts=markdown)

## [What Are Unknown Cyber Threats? (And Are They Really Unknown?)](https://www2.paloaltonetworks.com/blog/2016/12/unknown-threat/)

Most traditional security products are built to act based on known threats. The moment they see something that is known to be malicious, they block it. To get past security product...  
Dec 01, 2016  
By [Karin Shopen](https://www.paloaltonetworks.com/blog/author/karin-shopen/?ts=markdown "Posts by Karin Shopen")  
[](https://www2.paloaltonetworks.com/blog/2015/07/ups-observations-on-cve-2015-3113-prior-zero-days-and-the-pirpi-payload/)  
[Malware](https://www.paloaltonetworks.com/blog/category/malware-2/?ts=markdown), [Threat Prevention](https://www.paloaltonetworks.com/blog/category/threat-prevention-2/?ts=markdown), [Unit 42](https://unit42-dev2.paloaltonetworks.com)

## [UPS: Observations on CVE-2015-3113, Prior Zero-Days and the Pirpi Payload](https://www2.paloaltonetworks.com/blog/2015/07/ups-observations-on-cve-2015-3113-prior-zero-days-and-the-pirpi-payload/)

A June 23 FireEye blog post titled "Operation Clandestine Wolf" discussed a cyber espionage group, known as APT3, that had been exploiting a zero-day...  
Jul 27, 2015  
By [Robert Falcone](https://www.paloaltonetworks.com/blog/author/robert-falcone/?ts=markdown "Posts by Robert Falcone") and [Richard Wartell](https://www.paloaltonetworks.com/blog/author/richard-wartell/?ts=markdown "Posts by Richard Wartell")

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