Vulnerability · Published Feb 25, 2021 · Assigned by microsoft
CVE-2021-1730Microsoft Exchange Server Spoofing Vulnerability
Medium 5.4
In plain English
A medium-severity security flaw in Microsoft Exchange Server 2016 Cumulative Update 18 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.8% (higher than 79% of all known vulnerabilities).
Official description
<p>A spoofing vulnerability exists in Microsoft Exchange Server which could result in an attack that would allow a malicious actor to impersonate the user.</p> <p>This update addresses this vulnerability.</p> <p>To prevent these types of attacks, Microsoft recommends customers to download inline images from different DNSdomains than the rest of OWA. Please see further instructions in the FAQ to put in place this mitigations.</p>
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 7 | 15.02.0 – before publication |
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 18 | 15.01.0 – before publication |