Input validation error in Microsoft Exchange Server - CVE-2021-26858
Published: March 2, 2021 / Updated: April 1, 2021
Vulnerability identifier: #VU51169
CSH Severity: Critical
CVSS v4: 8.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2021-26858
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
The vulnerability is being exploited in the wild
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code on the system.
The vulnerability exists due to insufficient validation of user-supplied input. A remote attacker can send specially crafted data to the Exchange server and execute arbitrary code on the system.
Note, this vulnerability is being actively exploited in the wild.
Affected software
Microsoft Exchange Server
How to mitigate CVE-2021-26858
Install updates from vendor's website.