CVE-2021-1730
mediumpriority · track · 24EPSS 0.018 · 79 %ileEURUUSEPSS · scored 2026-10-27
<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>
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
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affected products (6)
Products and version ranges known to be affected.
also known as (4)
Other names and identifiers for this entity.
sources
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references (6)
External citations — patches, advisories, analysis.
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-1730cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2021-1730cnnvd
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-1730cnnvd
- https://vigilance.fr/vulnerability/Microsoft-Exchange-vulnerabilities-of-February-2021-34530cnnvd
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-1730enisa_euvd
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-1730PatchVendor Advisorynvd
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