CVE-2021-26858High· 7.8▾ Abyssal⚠ Exploited in the wildPoC availableMicrosoft Exchange Server Remote Code Execution Vulnerability
▾ Abyssal zone — Critical with a public exploit or in-the-wild use
impact 42.9 · likelihood 18.7 · exploitation 25 · ransomware 5
A public proof-of-concept already exists for this vulnerability — see Exploit availability below.
Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake.
Exploit-prediction probability, daily snapshots since Aug 12.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Federal remediation due May 3, 2022
90%
90% → 94%
Last analysed / modified upstream
Exploit / PoC code exists
Added to the CISA catalog on Nov 3, 2021. Federal remediation due May 3, 2022. View catalog ↗
Microsoft Exchange Server Remote Code Execution Vulnerability
exchange_server = 2013exchange_server = 2016exchange_server = 2019Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
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