Microsoft Exchange Server
CVE-2021-24085 — Microsoft Exchange Server Spoofing Vulnerability
Executive Summary
None
Overview
6.5
CVSS MEDIUM
Important
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L/E:U/RL:O/RC:C
ATTACK VECTOR
Network
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
Low
USER INTERACTION
Required
SCOPE
Changed
CONFIDENTIALITY
Low
INTEGRITY
Low
AVAILABILITY
Low
EXPLOIT CODE MATURITY
Unproven
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 5.7
EPSS Score
0.04627
probability of exploitation in the next 30 days
0.9089 percentile - updated 2026-08-14
View on FIRST.org
Affected Products
4 affected products
| Product | KB Article | Severity | Impact | Restart Required |
|---|---|---|---|---|
| Microsoft Exchange Server 2016 Cumulative Update 18 | 4602269 (Security Update) |
Important | Spoofing | Maybe |
| Microsoft Exchange Server 2016 Cumulative Update 19 | 4602269 (Security Update) |
Important | Spoofing | Maybe |
| Microsoft Exchange Server 2019 Cumulative Update 7 | 4602269 (Security Update) |
Important | Spoofing | Maybe |
| Microsoft Exchange Server 2019 Cumulative Update 8 | 4602269 (Security Update) |
Important | Spoofing | Maybe |
Patches
1 patch
| Article | Type | Restart |
|---|---|---|
4602269 |
Security Update | Maybe |
Exploits & PoC
1 public PoCUnverified third-party code
Public proof-of-concept repositories aggregated from PoC-in-GitHub. They are not reviewed and may be incomplete, non-functional, or malicious — inspect the code before running anything.
| Repository | Stars | Published | Description |
|---|---|---|---|
| sourceincite/CVE-2021-24085 | 71 | 2021-02-15 |
Detection Rules
Detection availableCommunity detection & vulnerability-scanning rules aggregated from Sigma and Nuclei templates. Validate and tune to your environment before deploying.
Sigma rules 1
Acknowledgments
Steven Seeley (mr_me) of Source Incite Source Incite
References
On This Page