CVE-2023-35311
Microsoft Outlook Security Feature Bypass Vulnerability
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it. If you run Microsoft 365, fix it now.
CISA required action: Apply updates per vendor instructions or discontinue use of the product if updates are unavailable.
US federal civilian agencies must remediate by Aug 1, 2023.
Patch status
Official fix available since
Apply the vendor's update to every affected system. Check the fixed-in versions below where known.
Basis: NVD patch reference
Description
Microsoft Outlook Security Feature Bypass Vulnerability
Source: NIST National Vulnerability Database. Official vulnerability data, reproduced as published.
Affected products
| Product | Vendor | Affected versions | Source |
|---|---|---|---|
| Microsoft 365 | Microsoft | 2013; 2016 | KEV |
| Office | Microsoft | 2019 | NVD |
Sources: KEV = CISA Known Exploited Vulnerabilities catalog; NVD = NIST National Vulnerability Database.
Intelligence timeline
Developments from the last 30 days, newest first.
- CVSS scoredUpdateKEV
CVE-2023-35311 scored CVSS 8.8: Microsoft Outlook, Microsoft Outlook Security Feature Bypass Vulnerability
CISA lists this as exploited in the wild. Unpatched Outlook systems are exposed to active attacks now.
Basis: NIST National Vulnerability Database
- Patch releasedUpdateKEV
Patch released for CVE-2023-35311: Microsoft Outlook, Microsoft Outlook Security Feature Bypass Vulnerability
An official fix is now available for Microsoft Outlook. This vulnerability is being exploited, so apply it promptly.
Basis: NVD patch reference
1 earlier event is available with a subscription. See plans.
Coverage
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