Security News > 2022 > October > Microsoft updates mitigation for ProxyNotShell Exchange zero days
Microsoft has updated the mitigations for the latest Exchange zero-day vulnerabilities tracked as CVE-2022-41040 and CVE-2022-41082, also referred to ProxyNotShell.
Reported privately to Microsoft three weeks ago, CVE-2022-41040 is a server-side request forgery that enables privilege escalation and works with CVE-2022-41082 to trigger remote code execution on on-premise Exchange server deployments.
Since the proposed URL blocking rule was too specific, adversaries could still exploit the Exchange vulnerabilities in new attacks.
On Tuesday, Microsoft announced that it updated its advisories with the improved URL Rewrite rule, recommending Exchange Server customers review it and adopt one of the three mitigation options provided.
Customers with Exchange Emergency Mitigation Service enabled benefit automatically from the updated URL Rewrite mitigation for Exchange Server 2016 and Exchange Server 2019.
It is worth noting that Microsoft provides these mitigations for customers with on-premise Exchange servers, which means that companies with a hybrid deployment are also at risk.
News URL
Related news
- Microsoft October 2024 Patch Tuesday fixes 5 zero-days, 118 flaws (source)
- Microsoft patches two zero-days exploited in the wild (CVE-2024-43573, CVE-2024-43572) (source)
- Week in review: Microsoft fixes two exploited zero-days, SOC teams are losing trust in security tools (source)
- Microsoft November 2024 Patch Tuesday fixes 4 zero-days, 91 flaws (source)
- Microsoft November 2024 Patch Tuesday fixes 4 zero-days, 89 flaws (source)
- Microsoft fixes actively exploited zero-days (CVE-2024-43451, CVE-2024-49039) (source)
- Microsoft Exchange adds warning to emails abusing spoofing flaw (source)
- Microsoft patches Windows zero-day exploited in attacks on Ukraine (source)
- Microsoft pulls Exchange security updates over mail delivery issues (source)
- Microsoft launches Zero Day Quest hacking event with $4 million in rewards (source)
Related Vulnerability
| DATE | CVE | VULNERABILITY TITLE | RISK |
|---|---|---|---|
| 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 |