CVE-2021-31209
Microsoft Exchange Server Spoofing Vulnerability
Severity Score
6.5
*CVSS v3.1
Exploit Likelihood
*EPSS
Affected Versions
*CPE
Public Exploits
0
*Multiple Sources
Exploited in Wild
-
*KEV
Decision
Track
*SSVC
Descriptions
Microsoft Exchange Server Spoofing Vulnerability
Una vulnerabilidad de Suplantación de Identidad de Microsoft Exchange Server
This vulnerability allows network-adjacent attackers to tamper with update data on affected installations of Microsoft Exchange Server. User interaction is required to exploit this vulnerability.
The specific flaw exists within the handling of Exchange Server Help updates. The issue results from a missing integrity check on update downloads. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of SYSTEM.
*Credits:
Steven Seeley (mr_me) of Source Incite
CVSS Scores
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
* Common Vulnerability Scoring System
SSVC
- Decision:Track
Exploitation
Automatable
Tech. Impact
* Organization's Worst-case Scenario
Timeline
- 2021-04-14 CVE Reserved
- 2021-05-11 CVE Published
- 2025-02-28 CVE Updated
- 2025-03-30 EPSS Updated
- ---------- Exploited in Wild
- ---------- KEV Due Date
- ---------- First Exploit
CWE
- CWE-290: Authentication Bypass by Spoofing
CAPEC
References (2)
| URL | Tag | Source |
|---|---|---|
| https://www.zerodayinitiative.com/advisories/ZDI-21-615 | Third Party Advisory |
|
| URL | Date | SRC |
|---|
| URL | Date | SRC |
|---|---|---|
| https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31209 | 2023-08-02 |
| URL | Date | SRC |
|---|
Affected Vendors, Products, and Versions
| Vendor | Product | Version | Other | Status | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Vendor | Product | Version | Other | Status | <-- --> | Vendor | Product | Version | Other | Status |
| Microsoft Search vendor "Microsoft" | Exchange Server Search vendor "Microsoft" for product "Exchange Server" | 2013 Search vendor "Microsoft" for product "Exchange Server" and version "2013" | cumulative_update_23 |
Affected
| ||||||
| Microsoft Search vendor "Microsoft" | Exchange Server Search vendor "Microsoft" for product "Exchange Server" | 2016 Search vendor "Microsoft" for product "Exchange Server" and version "2016" | cumulative_update_19 |
Affected
| ||||||
| Microsoft Search vendor "Microsoft" | Exchange Server Search vendor "Microsoft" for product "Exchange Server" | 2016 Search vendor "Microsoft" for product "Exchange Server" and version "2016" | cumulative_update_20 |
Affected
| ||||||
| Microsoft Search vendor "Microsoft" | Exchange Server Search vendor "Microsoft" for product "Exchange Server" | 2019 Search vendor "Microsoft" for product "Exchange Server" and version "2019" | cumulative_update_8 |
Affected
| ||||||
| Microsoft Search vendor "Microsoft" | Exchange Server Search vendor "Microsoft" for product "Exchange Server" | 2019 Search vendor "Microsoft" for product "Exchange Server" and version "2019" | cumulative_update_9 |
Affected
| ||||||