CRITICAL CISA KEV
CVE-2021-26855
CVSS v3
9.1
CRITICAL
EPSS Score
94.3 %
exploit probability
CISA KEV
Yes
known exploited
Exploitation
—
SSVC status
Description
Microsoft Exchange Server Remote Code Execution Vulnerability
CISA Known Exploited Vulnerability
- Date Added
- 2021-11-03
- Patch Due Date
- 2022-05-03
- Ransomware Use
- Known
Frequently asked questions
What is CVE-2021-26855?
Microsoft Exchange Server Remote Code Execution Vulnerability
Is CVE-2021-26855 actively exploited?
Yes. CVE-2021-26855 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 2022-05-03.
What is the CVSS score for CVE-2021-26855?
CVE-2021-26855 has a CVSS v3 base score of 9.1 (CRITICAL severity).
Is CVE-2021-26855 affecting your environment?
Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.
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