CVE-2021-34453
HIGHCVSS 7.5/10EPSS 2.67%
Last modified
CVE-2021-34453 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Microsoft Exchange Server Denial of Service Vulnerability. EPSS estimates a 2.67% chance of exploitation in the next 30 days.
Description
Microsoft Exchange Server Denial of Service Vulnerability
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| 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-2021-34453Patch, Vendor Advisory
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34453Patch, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is CVE-2021-34453?
Microsoft Exchange Server Denial of Service Vulnerability
How severe is CVE-2021-34453?
CVE-2021-34453 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 2.67% probability of exploitation in the next 30 days.
How do I fix CVE-2021-34453?
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-2021-34448Scripting Engine Memory Corruption Vulnerability6.8
- CVE-2021-34449Win32k Elevation of Privilege Vulnerability7
- CVE-2021-3445A flaw was found in libdnf's signature verification function…7.5
- CVE-2021-34450Windows Hyper-V Remote Code Execution Vulnerability8.5
- CVE-2021-34451Microsoft Office Online Server Spoofing Vulnerability5.3
- CVE-2021-34452Microsoft Word Remote Code Execution Vulnerability7.8
- CVE-2021-34454Windows Remote Access Connection Manager Information Disclos…5.5
- CVE-2021-34455Windows File History Service Elevation of Privilege Vulnerab…7.8
- CVE-2021-34456Windows Remote Access Connection Manager Elevation of Privil…7.8
- CVE-2021-34457Windows Remote Access Connection Manager Information Disclos…5.5
- CVE-2021-34458Windows Kernel Remote Code Execution Vulnerability9.9
- CVE-2021-34459Windows AppContainer Elevation Of Privilege Vulnerability7.8
Are you affected by CVE-2021-34453?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST