Jan 28, 2023Ravie LakshmananEmail Security / Cyber Threat Microsoft is urging customers to keep their Exchange servers updated as well as take steps to bolster the environment, such as enabling Windows Extended Protection and configuring certificate-based signing of PowerShell serialization payloads. "Attackers looking to exploit unpatched Exchange servers are not going to go … [Read more...] about Microsoft Urges Customers to Secure On-Premises Exchange Servers
Exchange
Ransomware Hackers Using New Way to Bypass MS Exchange ProxyNotShell Mitigations
Dec 21, 2022Ravie LakshmananEmail Security / Data Security Threat actors affiliated with a ransomware strain known as Play are leveraging a never-before-seen exploit chain that bypasses blocking rules for ProxyNotShell flaws in Microsoft Exchange Server to achieve remote code execution (RCE) through Outlook Web Access (OWA). "The new exploit method bypasses URL rewrite … [Read more...] about Ransomware Hackers Using New Way to Bypass MS Exchange ProxyNotShell Mitigations
Microsoft Issues Improved Mitigations for Unpatched Exchange Server Vulnerabilities
Microsoft on Friday disclosed it has made more improvements to the mitigation method offered as a means to prevent exploitation attempts against the newly disclosed unpatched security flaws in Exchange Server. To that end, the tech giant has revised the blocking rule in IIS Manager from ".*autodiscover\.json.*Powershell.*" to "(?=.*autodiscover\.json)(?=.*powershell)." The … [Read more...] about Microsoft Issues Improved Mitigations for Unpatched Exchange Server Vulnerabilities
State-Sponsored Hackers Likely Exploited MS Exchange 0-Days Against ~10 Organizations
Microsoft on Friday disclosed that a single activity group in August 2022 achieved initial access and breached Exchange servers by chaining the two newly disclosed zero-day flaws in a limited set of attacks aimed at less than 10 organizations globally. "These attacks installed the Chopper web shell to facilitate hands-on-keyboard access, which the attackers used to perform … [Read more...] about State-Sponsored Hackers Likely Exploited MS Exchange 0-Days Against ~10 Organizations
Favorable exchange rate on a fake cryptoexchange
Online scammers use all sorts of ways to separate cryptoinvestors from their prized bitcoin. They create fake news sites and promise helicopter money. They even post screenshots in Lightshot with “cryptowallet login credentials” — this being a trap for folks who have a weakness for other folks’ secrets and a free lunch. We recently uncovered a new scheme in which YouTube users … [Read more...] about Favorable exchange rate on a fake cryptoexchange
New ToddyCat Hacker Group on Experts’ Radar After Targeting MS Exchange Servers
An advanced persistent threat (APT) actor codenamed ToddyCat has been linked to a string of attacks aimed at high-profile entities in Europe and Asia since at least December 2020. The relatively new adversarial collective is said to have commenced its operations by targeting Microsoft Exchange servers in Taiwan and Vietnam using an unknown exploit to deploy the China Chopper … [Read more...] about New ToddyCat Hacker Group on Experts’ Radar After Targeting MS Exchange Servers
Hackers Hijack Email Reply Chains on Unpatched Exchange Servers to Spread Malware
A new email phishing campaign has been spotted leveraging the tactic of conversation hijacking to deliver the IcedID info-stealing malware onto infected machines by making use of unpatched and publicly-exposed Microsoft Exchange servers. "The emails use a social engineering technique of conversation hijacking (also known as thread hijacking)," Israeli company Intezer said in a … [Read more...] about Hackers Hijack Email Reply Chains on Unpatched Exchange Servers to Spread Malware
Microsoft Exchange Bug Exposes ~100,000 Windows Domain Credentials
An unpatched design flaw in the implementation of Microsoft Exchange's Autodiscover protocol has resulted in the leak of approximately 100,000 login names and passwords for Windows domains worldwide. "This is a severe security issue, since if an attacker can control such domains or has the ability to 'sniff' traffic in the same network, they can capture domain credentials in … [Read more...] about Microsoft Exchange Bug Exposes ~100,000 Windows Domain Credentials
Microsoft Exchange Under Attack With ProxyShell Flaws
The U.S. Cybersecurity and Infrastructure Security Agency is warning of active exploitation attempts that leverage the latest line of "ProxyShell" Microsoft Exchange vulnerabilities that were patched earlier this May, including deploying LockFile ransomware on compromised systems. Tracked as CVE-2021-34473, CVE-2021-34523, and CVE-2021-31207, the vulnerabilities enable … [Read more...] about Microsoft Exchange Under Attack With ProxyShell Flaws
Attack on DEX exchange clients in Discord
Following recent scams involving fake cryptocurrency exchanges and fake news sites, we recently uncovered a third campaign, one using fake DEX exchanges and aimed at cryptocurrency enthusiasts on the Discord messaging app. Here’s how the new scheme works. A word about cryptocurrency exchanges First, what’s a DEX? Two types of cryptocurrency exchanges exist: centralized (CEX) … [Read more...] about Attack on DEX exchange clients in Discord