CVE-2021-42305
MEDIUMCVSS 6.5/10EPSS 8.11%
Last modified
CVE-2021-42305 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. Microsoft Exchange Server Spoofing Vulnerability. EPSS estimates a 8.11% chance of exploitation in the next 30 days.
Description
Microsoft Exchange Server Spoofing Vulnerability
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Microsoft | Exchange Server | 2013 | Cumulative Update 23 |
| Microsoft | Exchange Server | 2016 | Cumulative Update 21 |
| Microsoft | Exchange Server | 2019 | Cumulative Update 10 |
References
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42305Patch, Vendor Advisory
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42305Patch, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is CVE-2021-42305?
Microsoft Exchange Server Spoofing Vulnerability
How severe is CVE-2021-42305?
CVE-2021-42305 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 8.11% probability of exploitation in the next 30 days.
How do I fix CVE-2021-42305?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2021
- CVE-2021-4230A vulnerability has been found in Airfield Online and classi…7.5
- CVE-2021-42300Azure Sphere Tampering Vulnerability6
- CVE-2021-42301Azure RTOS Information Disclosure Vulnerability3.3
- CVE-2021-42302Azure RTOS Elevation of Privilege Vulnerability6.6
- CVE-2021-42303Azure RTOS Elevation of Privilege Vulnerability6.6
- CVE-2021-42304Azure RTOS Elevation of Privilege Vulnerability6.6
- CVE-2021-42306An information disclosure vulnerability manifests when a use…8.1
- CVE-2021-42307Microsoft Edge (Chromium-based) Information Disclosure Vulne…4.3
- CVE-2021-42308Microsoft Edge (Chromium-based) Spoofing Vulnerability3.1
- CVE-2021-42309Microsoft SharePoint Server Remote Code Execution Vulnerabil…8.8
- CVE-2021-4231A vulnerability was found in Angular up to 11.0.4/11.1.0-nex…5.4
- CVE-2021-42310Microsoft Defender for IoT Remote Code Execution Vulnerabili…9.8
Are you affected by CVE-2021-42305?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST