CVE•Published 2021-07-14•Modified 2026-08-10•3 articles on news•6 live references•NVD data

CVE-2021-34523Microsoft · Exchange_server

Vulnerability data via NVD (ingested)

CVSS v3.1

9.0

CRITICAL

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N

EPSS percentile

100

Exploit Prediction Scoring System · top 0% of all CVEs

Description

Microsoft Exchange Server Elevation of Privilege Vulnerability

Timeline

Published 2021-07-14

Modified 2026-08-10

External references

NVD MITRE Exploit-DB GitHub PoC trickest/cve VulnCheck

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 tag931 hosts

vuln:CVE-2021-34523

Hosts Shodan has explicitly fingerprinted as vulnerable.

Shodan · product + version

product:"Microsoft Exchange Server" version:"2013"

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-2021-34523

Country / ASN / product breakdown for the vuln query.

Censys

vulnerabilities.cve_id: CVE-2021-34523

Censys host search filtered to this CVE id.

grep.app

CVE-2021-34523

Public source-code mentions — fast PoC discovery.

GitHub code

CVE-2021-34523

GitHub code search for direct mentions.

Google dork

"CVE-2021-34523" exploit -site:nvd.nist.gov

Write-ups and news, NVD excluded.

Known PoCs on GitHub (4)

CVE-2021-345234 repos

GhostTroops/TOPShell

TOP All bugbounty pentesting CVE-2023- POC Exp RCE example payload Things

★ 732·updated today

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.

★ 619·updated 5d ago

signorrayan/RedTeam_toolkitPython

Red Team Toolkit is an Open-Source Django Offensive Web-App which is keeping the useful offensive tools used in the red-teaming together.

★ 575·updated 7mo ago

kh4sh3i/exchange-penetration-testingPowerShell

The great Microsoft exchange hack: A penetration tester’s guide (exchange penetration testing)

★ 145·updated 3mo ago