Security News > 2022 > December > New Microsoft Exchange exploit chain lets ransomware attackers in (CVE-2022-41080)
Ransomware-wielding attackers are using a new exploit chain that includes one of the ProxyNotShell vulnerabilities to achieve remote code execution on Microsoft Exchange servers.
The ProxyNotShell exploit chain used CVE-2022-41040, a SSRF vulnerability in the Autodiscover endpoint of Microsoft Exchange, while this new one uses CVE-2022-41080 to achieve privilege escalation through Outlook Web Access.
The exploit chain - dubbed OWASSRF by Crowdstrike researchers - can only be headed off by implementing the patches for Microsoft Exchange released in November 2022.
The researchers spotted in-the-wild exploitation of CVE-2022-41082 when investigating Play ransomware intrusions where the common entry vector was Microsoft Exchange.
In the meantime, Huntress Labs threat researcher Dray Agha managed to grab attack tools via an open repository and among them was a PoC script leveraging an unknown OWA exploit technique and the CVE-2022-41082 exploit.
"After initial access via this new exploit method, the threat actor leveraged legitimate Plink and AnyDesk executables to maintain access, and performed anti-forensics techniques on the Microsoft Exchange server in an attempt to hide their activity," Crowdstrike researchers concluded, and provided additional advice for mitigating the risk and detecting signs of exploitation.
News URL
https://www.helpnetsecurity.com/2022/12/21/cve-2022-41080/
Related news
- Microsoft Identifies Storm-0501 as Major Threat in Hybrid Cloud Ransomware Attacks (source)
- Ransomware gang using stolen Microsoft Entra ID creds to bust into the cloud (source)
- Ransomware attackers hop from on-premises systems to cloud to compromise Microsoft 365 accounts (source)
- Akira and Fog ransomware now exploit critical Veeam RCE flaw (source)
- Microsoft says more ransomware stopped before reaching encryption (source)
- Microsoft: Ransomware Attacks Growing More Dangerous, Complex (source)
- Microsoft SharePoint RCE flaw exploits in the wild – you've had 3 months to patch (source)
- Black Basta ransomware poses as IT support on Microsoft Teams to breach networks (source)
- VEILDrive Attack Exploits Microsoft Services to Evade Detection and Distribute Malware (source)
- New Ymir Ransomware Exploits Memory for Stealthy Attacks; Targets Corporate Networks (source)
Related Vulnerability
DATE | CVE | VULNERABILITY TITLE | RISK |
---|---|---|---|
2022-11-09 | CVE-2022-41080 | Unspecified vulnerability in Microsoft Exchange Server 2013/2016/2019 Microsoft Exchange Server Elevation of Privilege Vulnerability | 8.8 |
2022-10-03 | CVE-2022-41082 | Deserialization of Untrusted Data vulnerability in Microsoft Exchange Server 2013/2016/2019 Microsoft Exchange Server Remote Code Execution Vulnerability | 8.0 |
2022-10-03 | CVE-2022-41040 | Server-Side Request Forgery (SSRF) vulnerability in Microsoft Exchange Server 2013/2016/2019 Microsoft Exchange Server Elevation of Privilege Vulnerability | 8.8 |