CVE•Published 2021-11-10•Modified 2026-08-19•1 article on news•5 live references•NVD data
CVE-2021-42321Microsoft · Exchange_server
Vulnerability data via NVD (ingested)
CVSS v3.1
8.8
HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS percentile
100
Exploit Prediction Scoring System · top 0% of all CVEs
Description
Microsoft Exchange Server Remote Code Execution Vulnerability
Timeline
Published 2021-11-10
Modified 2026-08-19
External references
Search for exposed instances
Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).
Shodan · vuln tag0 hosts
vuln:CVE-2021-42321Hosts Shodan has explicitly fingerprinted as vulnerable.
Shodan · product + version
product:"Microsoft Exchange Server" version:"2016"Version-pinned fingerprint from NVD's first vulnerable CPE.
Shodan · banner/body mention
http.html:"Exchange Server"HTTP body or banner mentions "Exchange Server" — catches deploys Shodan didn't identify as a product.
More intel sources (5)
Shodan report
vuln:CVE-2021-42321Country / ASN / product breakdown for the vuln query.
Censys
vulnerabilities.cve_id: CVE-2021-42321Censys host search filtered to this CVE id.
grep.app
CVE-2021-42321Public source-code mentions — fast PoC discovery.
GitHub code
CVE-2021-42321GitHub code search for direct mentions.
Google dork
"CVE-2021-42321" exploit -site:nvd.nist.govWrite-ups and news, NVD excluded.
Known PoCs on GitHub (4)
CVE-2021-423214 repos
Mr-xn/Penetration_Testing_POCHTML
渗透测试有关的POC、EXP、脚本、提权、小工具等---About penetration-testing python-script poc getshell csrf xss cms php-getshell domainmod-xss csrf-webshell cobub-razor cve rce sql sql-poc poc-exp bypas…
0xsyr0/OSCPPowerShell
OSCP Cheat Sheet
pwntester/ysoserial.netC#
Deserialization payload generator for a variety of .NET formatters
Ostorlab/KEVunknown
Ostorlab KEV: One-command to detect most remotely known exploitable vulnerabilities. Sourced from CISA KEV, Google's Tsunami, Ostorlab's Asteroid and Bug Bounty programs.