Live › vulnerability › CVE-2021-26857
Go to dashboardMicrosoft Exchange Server has an unspecified flaw in its code that allows remote code execution, and it is part of the ProxyLogon chain. Attackers can run code on the Exchange server, which is a known ransomware target, and it is actively exploited in the wild.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 19:11 UTC, 3h before NVD. All times on this page are UTC.
Apply updates per vendor instructions.
| Product | Ecosystem | Affected | Fixed in |
|---|---|---|---|
| Microsoft Exchange Server | vendor | – | – |
Unknown from the sources. In the analyst’s queue.
Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
Microsoft Exchange Server contains an unspecified vulnerability that allows for remote code execution. This vulnerability is part of the ProxyLogon exploit chain.
CISA required action: Apply updates per vendor instructions.
This page as .md · .json · in your agent: get_signal("CVE-2021-26857")
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