CVE-2021-26855Critical· 9.1▾ Hadal⚠ Exploited in the wild0dayPoC availableMicrosoft Exchange Server Remote Code Execution Vulnerability
▾ Hadal zone — Critical and actively exploited (CISA KEV / 0day)
impact 50.1 · likelihood 20 · exploitation 25 · ransomware 5
A public proof-of-concept already exists for this vulnerability — see Exploit availability below.
Public exploit / PoC code seen in 4 sources. Availability, not in-the-wild use.
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
Last analysed / modified upstream
100%
Exploit-DB · 51 GitHub repos · Metasploit ×3 · Nuclei ×1 (last check)
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.
Connected by shared product, vendor, weakness, or advisory.
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