HIGHCVE-2026-21511Published Modified CNA microsoft
CVE-2026-21511: Microsoft Outlook Spoofing Vulnerability
Deserialization of untrusted data in Microsoft Office Outlook allows an unauthorized attacker to perform spoofing over a network.
Metrics
- CVSS v3.1
- 7.5
- Severity
- HIGH
- Fixed in
- 16.0.5539.1002
- Affected Products
- 10
Fix available
16.0.5539.100216.0.10417.2009716.0.19127.2051816.106.26020821https://aka.ms/OfficeSecurityReleases
Patch commits
Affected packages
- Microsoft / Microsoft 365 Apps for Enterprise< https://aka.ms/OfficeSecurityReleases (from 16.0.1)
- Microsoft / Microsoft Office 2019< https://aka.ms/OfficeSecurityReleases (from 19.0.0)
- Microsoft / Microsoft Office LTSC 2021< https://aka.ms/OfficeSecurityReleases (from 16.0.1)
- Microsoft / Microsoft Office LTSC 2024< https://aka.ms/OfficeSecurityReleases (from 16.0.0)
- Microsoft / Microsoft Office LTSC for Mac 2021< 16.106.26020821 (from 16.0.1)
- Microsoft / Microsoft Office LTSC for Mac 2024< 16.106.26020821 (from 16.0.0)
- Microsoft / Microsoft SharePoint Enterprise Server 2016< 16.0.5539.1002 (from 16.0.0)
- Microsoft / Microsoft SharePoint Server 2019< 16.0.10417.20097 (from 16.0.0)
- Microsoft / Microsoft SharePoint Server Subscription Edition< 16.0.19127.20518 (from 16.0.0)
- Microsoft / Microsoft Word 2016< 16.0.5539.1002 (from 16.0.1)
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:CReferences