Vulnerability · Published Sep 8, 2026 · Assigned by microsoft
CVE-2026-77491Windows GDI Information Disclosure Vulnerability
Medium 5.5
In plain English
A medium-severity out-of-bounds read in Microsoft Office 365 for Mac from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 38% of all known vulnerabilities).
Severity (CVSS 3.1)5.5Medium
Exploit odds (30 days)0.4%top 62.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Out-of-bounds read in Windows GDI allows an unauthorized attacker to disclose information locally.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Microsoft Office 365 for Mac | 1.0.0 – before 16.112.26090911 |
| Microsoft | Microsoft Office for Android | 16.0.1 – before 16.0.20430.20000 |
| Microsoft | Microsoft Office LTSC for Mac 2021 | 16.0.1 – before 16.112.26090911 |
| Microsoft | Microsoft Office LTSC for Mac 2024 | 16.0.0 – before 16.112.26090911 |
| Microsoft | Windows 10 Version 1607 | 10.0.14393.0 – before 10.0.14393.9512 |
| Microsoft | Windows 10 Version 1809 | 10.0.17763.0 – before 10.0.17763.9245 |
| Microsoft | Windows 10 Version 21H2 | 10.0.19044.0 – before 10.0.19044.7725 |
| Microsoft | Windows 10 Version 22H2 | 10.0.19045.0 – before 10.0.19045.7725 |
| Microsoft | Windows 11 version 23H2 | 10.0.22631.0 – before 10.0.22631.7582 |
| Microsoft | Windows 11 Version 23H2 | 10.0.22631.0 – before 10.0.22631.7582 |
| Microsoft | Windows 11 Version 24H2 | 10.0.26100.0 – before 10.0.26100.9445 |
| Microsoft | Windows 11 Version 25H2 | 10.0.26200.0 – before 10.0.26200.9445 |
| Microsoft | Windows 11 version 26H1 | 10.0.28000.0 – before 10.0.28000.2954 |
| Microsoft | Windows Server 2012 | 6.2.9200.0 – before 6.2.9200.26349 |
| Microsoft | Windows Server 2012 (Server Core installation) | 6.2.9200.0 – before 6.2.9200.26349 |
| Microsoft | Windows Server 2012 R2 | 6.3.9600.0 – before 6.3.9600.23398 |
| Microsoft | Windows Server 2012 R2 (Server Core installation) | 6.3.9600.0 – before 6.3.9600.23398 |
| Microsoft | Windows Server 2016 | 10.0.14393.0 – before 10.0.14393.9512 |
| Microsoft | Windows Server 2016 (Server Core installation) | 10.0.14393.0 – before 10.0.14393.9512 |
| Microsoft | Windows Server 2019 | 10.0.17763.0 – before 10.0.17763.9245 |
| Microsoft | Windows Server 2019 (Server Core installation) | 10.0.17763.0 – before 10.0.17763.9245 |
| Microsoft | Windows Server 2022 | 10.0.20348.0 – before 10.0.20348.5622 |
| Microsoft | Windows Server 2025 | 10.0.26100.0 – before 10.0.26100.33438 |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 – before 10.0.26100.33438 |
Weakness: CWE-125 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C
References
- Windows GDI Information Disclosure Vulnerability vendor-advisory, patch