Security News > 2021 > May > Microsoft May 2021 Patch Tuesday fixes 55 flaws, 3 zero-days
2021-05-11 17:28
Today is Microsoft's May 2021 Patch Tuesday, and with it comes three zero-day vulnerabilities, so Windows admins will be rushing to apply updates.
With today's update, Microsoft has fixed 55 vulnerabilities, with four classified as Critical, 50 as Important, and one as Moderate.
As part of today's Patch Tuesday, Microsoft has fixed three publicly disclosed vulnerabilities.
The CVE-2021-31207 Microsoft Exchange vulnerability was used by in the 2021 Pwn2Own hacking challenge.
It is expected that threat actors will analyze the patches to create exploits for the vulnerabilities, especially the one for Microsoft Exchange.
Below is the full list of resolved vulnerabilities and released advisories in the May 2021 Patch Tuesday updates.
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Related Vulnerability
| DATE | CVE | VULNERABILITY TITLE | RISK |
|---|---|---|---|
| 2021-05-11 | CVE-2021-31207 | Unrestricted Upload of File with Dangerous Type vulnerability in Microsoft Exchange Server 2013/2016/2019 Microsoft Exchange Server Security Feature Bypass Vulnerability | 0.0 |