Heap overflow in Windows Rich Text Edit Control allows code execution
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-122 and the CVSS impact.
Summary
The Windows Rich Text Edit Control and several Microsoft products, including Microsoft 365 Apps for Enterprise, Microsoft Office 365 for Mac, Microsoft Office LTSC 2021, Microsoft Office LTSC 2024 and Microsoft Office LTSC for Mac 2021, and other products, are affected. A heap-based buffer overflow (CWE-122) lets an unauthorized attacker execute code over a network.
Written with Claude Haiku 5.5 from the sources below · 2026-10-27
Description from the CNA
Heap-based buffer overflow in Windows Rich Text Edit Control allows an unauthorized attacker to execute code over a network.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Microsoft | Microsoft 365 Apps for Enterprise | 16.0.1 to before https://aka.ms/OfficeSecurityReleases | https://aka.ms/OfficeSecurityReleases | Patch available | CNA |
| Microsoft | Microsoft Office 365 for Mac | 1.0.0 to before 16.114.26101123 | 16.114.26101123 | Patch available | CNA |
| Microsoft | Microsoft Office LTSC 2021 | 16.0.1 to before 16.0.14334.20974 | 16.0.14334.20974 | Patch available | CNA |
| Microsoft | Microsoft Office LTSC 2024 | 16.0.0 to before 16.0.17932.21056 | 16.0.17932.21056 | Patch available | CNA |
| Microsoft | Microsoft Office LTSC for Mac 2021 | 16.0.1 to before 16.114.26101123 | 16.114.26101123 | Patch available | CNA |
| Microsoft | Microsoft Office LTSC for Mac 2024 | 16.0.0 to before 16.114.26101123 | 16.114.26101123 | Patch available | CNA |
| Microsoft | Windows 10 Version 1607 | 10.0.14393.0 to before 10.0.14393.9612 | 10.0.14393.9612 | Patch available | CNA |
| Microsoft | Windows 10 Version 1809 | 10.0.17763.0 to before 10.0.17763.9376 | 10.0.17763.9376 | Patch available | CNA |
| Microsoft | Windows 10 Version 21H2 | 10.0.19044.0 to before 10.0.19044.7807 | 10.0.19044.7807 | Patch available | CNA |
| Microsoft | Windows 10 Version 22H2 | 10.0.19045.0 to before 10.0.19045.7807 | 10.0.19045.7807 | Patch available | CNA |
| Microsoft | Windows 11 version 23H2 | 10.0.22631.0 to before 10.0.22631.7652 | 10.0.22631.7652 | Patch available | CNA |
| Microsoft | Windows 11 Version 23H2 | 10.0.22631.0 to before 10.0.22631.7652 | 10.0.22631.7652 | Patch available | CNA |
| Microsoft | Windows 11 Version 24H2 | 10.0.26100.0 to before 10.0.26100.9711 | 10.0.26100.9711 | Patch available | CNA |
| Microsoft | Windows 11 Version 25H2 | 10.0.26200.0 to before 10.0.26200.9711 | 10.0.26200.9711 | Patch available | CNA |
| Microsoft | Windows 11 version 26H1 | 10.0.28000.0 to before 10.0.28000.3231 | 10.0.28000.3231 | Patch available | CNA |
| Microsoft | Windows 11 Version 26H2 | 10.0.26300.0 to before 10.0.26300.9711 | 10.0.26300.9711 | Patch available | CNA |
| Microsoft | Windows Server 2012 | 6.2.9200.0 to before 6.2.9200.26434 | 6.2.9200.26434 | Patch available | CNA |
| Microsoft | Windows Server 2012 (Server Core installation) | 6.2.9200.0 to before 6.2.9200.26434 | 6.2.9200.26434 | Patch available | CNA |
| Microsoft | Windows Server 2012 R2 | 6.3.9600.0 to before 6.3.9600.23470 | 6.3.9600.23470 | Patch available | CNA |
| Microsoft | Windows Server 2012 R2 (Server Core installation) | 6.3.9600.0 to before 6.3.9600.23470 | 6.3.9600.23470 | Patch available | CNA |
| Microsoft | Windows Server 2016 | 10.0.14393.0 to before 10.0.14393.9612 | 10.0.14393.9612 | Patch available | CNA |
| Microsoft | Windows Server 2016 (Server Core installation) | 10.0.14393.0 to before 10.0.14393.9612 | 10.0.14393.9612 | Patch available | CNA |
| Microsoft | Windows Server 2019 | 10.0.17763.0 to before 10.0.17763.9376 | 10.0.17763.9376 | Patch available | CNA |
| Microsoft | Windows Server 2019 (Server Core installation) | 10.0.17763.0 to before 10.0.17763.9376 | 10.0.17763.9376 | Patch available | CNA |
| Microsoft | Windows Server 2022 | 10.0.20348.0 to before 10.0.20348.5761 | 10.0.20348.5761 | Patch available | CNA |
| Microsoft | Windows Server 2025 | 10.0.26100.0 to before 10.0.26100.33650 | 10.0.26100.33650 | Patch available | CNA |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 to before 10.0.26100.33650 | 10.0.26100.33650 | Patch available | CNA |
- Microsoft 365 Apps for Enterprise VendorMicrosoft Affected 16.0.1 to before https://aka.ms/OfficeSecurityReleases Fixed in https://aka.ms/OfficeSecurityReleases Patch available CNA
- Microsoft Office 365 for Mac VendorMicrosoft Affected 1.0.0 to before 16.114.26101123 Fixed in 16.114.26101123 Patch available CNA
- Microsoft Office LTSC 2021 VendorMicrosoft Affected 16.0.1 to before 16.0.14334.20974 Fixed in 16.0.14334.20974 Patch available CNA
- Microsoft Office LTSC 2024 VendorMicrosoft Affected 16.0.0 to before 16.0.17932.21056 Fixed in 16.0.17932.21056 Patch available CNA
- Microsoft Office LTSC for Mac 2021 VendorMicrosoft Affected 16.0.1 to before 16.114.26101123 Fixed in 16.114.26101123 Patch available CNA
- Microsoft Office LTSC for Mac 2024 VendorMicrosoft Affected 16.0.0 to before 16.114.26101123 Fixed in 16.114.26101123 Patch available CNA
- Windows 10 Version 1607 VendorMicrosoft Affected 10.0.14393.0 to before 10.0.14393.9612 Fixed in 10.0.14393.9612 Patch available CNA
- Windows 10 Version 1809 VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.9376 Fixed in 10.0.17763.9376 Patch available CNA
- Windows 10 Version 21H2 VendorMicrosoft Affected 10.0.19044.0 to before 10.0.19044.7807 Fixed in 10.0.19044.7807 Patch available CNA
- Windows 10 Version 22H2 VendorMicrosoft Affected 10.0.19045.0 to before 10.0.19045.7807 Fixed in 10.0.19045.7807 Patch available CNA
- Windows 11 version 23H2 VendorMicrosoft Affected 10.0.22631.0 to before 10.0.22631.7652 Fixed in 10.0.22631.7652 Patch available CNA
- Windows 11 Version 23H2 VendorMicrosoft Affected 10.0.22631.0 to before 10.0.22631.7652 Fixed in 10.0.22631.7652 Patch available CNA
- Windows 11 Version 24H2 VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.9711 Fixed in 10.0.26100.9711 Patch available CNA
- Windows 11 Version 25H2 VendorMicrosoft Affected 10.0.26200.0 to before 10.0.26200.9711 Fixed in 10.0.26200.9711 Patch available CNA
- Windows 11 version 26H1 VendorMicrosoft Affected 10.0.28000.0 to before 10.0.28000.3231 Fixed in 10.0.28000.3231 Patch available CNA
- Windows 11 Version 26H2 VendorMicrosoft Affected 10.0.26300.0 to before 10.0.26300.9711 Fixed in 10.0.26300.9711 Patch available CNA
- Windows Server 2012 VendorMicrosoft Affected 6.2.9200.0 to before 6.2.9200.26434 Fixed in 6.2.9200.26434 Patch available CNA
- Windows Server 2012 (Server Core installation) VendorMicrosoft Affected 6.2.9200.0 to before 6.2.9200.26434 Fixed in 6.2.9200.26434 Patch available CNA
- Windows Server 2012 R2 VendorMicrosoft Affected 6.3.9600.0 to before 6.3.9600.23470 Fixed in 6.3.9600.23470 Patch available CNA
- Windows Server 2012 R2 (Server Core installation) VendorMicrosoft Affected 6.3.9600.0 to before 6.3.9600.23470 Fixed in 6.3.9600.23470 Patch available CNA
- Windows Server 2016 VendorMicrosoft Affected 10.0.14393.0 to before 10.0.14393.9612 Fixed in 10.0.14393.9612 Patch available CNA
- Windows Server 2016 (Server Core installation) VendorMicrosoft Affected 10.0.14393.0 to before 10.0.14393.9612 Fixed in 10.0.14393.9612 Patch available CNA
- Windows Server 2019 VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.9376 Fixed in 10.0.17763.9376 Patch available CNA
- Windows Server 2019 (Server Core installation) VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.9376 Fixed in 10.0.17763.9376 Patch available CNA
- Windows Server 2022 VendorMicrosoft Affected 10.0.20348.0 to before 10.0.20348.5761 Fixed in 10.0.20348.5761 Patch available CNA
- Windows Server 2025 VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.33650 Fixed in 10.0.26100.33650 Patch available CNA
- Windows Server 2025 (Server Core installation) VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.33650 Fixed in 10.0.26100.33650 Patch available CNA
CPE names Threatist (inferred) · 4
Inferred from how NVD named this product before; not given by a source.
Remediation
Install the Windows fixes 10.0.14393.9612 (Version 1607), 10.0.17763.9376 (Version 1809), 10.0.19044.7807 (21H2), 10.0.19045.7807 (22H2), 10.0.22631.7652 (23H2), 10.0.26100.9711 (24H2), 10.0.26200.9711 (25H2) and 10.0.28000.3231 (26H1). Install the Office fixes 16.114.26101123 for Microsoft Office 365 for Mac and Microsoft Office LTSC for Mac 2021 and 2024, 16.0.14334.20974 for Microsoft Office LTSC 2021, and 16.0.17932.21056 for Microsoft Office LTSC 2024. Microsoft 365 Apps for Enterprise is fixed in the Office security releases that Microsoft publishes on its Office security releases page.
Written with Claude Haiku 5.5 from the sources below · 2026-10-27
- Fix · CNA Microsoft 365 Apps for Enterprise (Microsoft) Fixed in https://aka.ms/OfficeSecurityReleases
- Fix · CNA Microsoft Office 365 for Mac (Microsoft) Fixed in 16.114.26101123
- Fix · CNA Microsoft Office LTSC 2021 (Microsoft) Fixed in 16.0.14334.20974
- Fix · CNA Microsoft Office LTSC 2024 (Microsoft) Fixed in 16.0.17932.21056
- Fix · CNA Microsoft Office LTSC for Mac 2021 (Microsoft) Fixed in 16.114.26101123
- Fix · CNA Microsoft Office LTSC for Mac 2024 (Microsoft) Fixed in 16.114.26101123
- Fix · CNA Windows 10 Version 1607 (Microsoft) Fixed in 10.0.14393.9612
- Fix · CNA Windows 10 Version 1809 (Microsoft) Fixed in 10.0.17763.9376
- Fix · CNA Windows 10 Version 21H2 (Microsoft) Fixed in 10.0.19044.7807
- Fix · CNA Windows 10 Version 22H2 (Microsoft) Fixed in 10.0.19045.7807
- Fix · CNA Windows 11 version 23H2 (Microsoft) Fixed in 10.0.22631.7652
- Fix · CNA Windows 11 Version 23H2 (Microsoft) Fixed in 10.0.22631.7652
- Fix · CNA Windows 11 Version 24H2 (Microsoft) Fixed in 10.0.26100.9711
- Fix · CNA Windows 11 Version 25H2 (Microsoft) Fixed in 10.0.26200.9711
- Fix · CNA Windows 11 version 26H1 (Microsoft) Fixed in 10.0.28000.3231
- Fix · CNA Windows 11 Version 26H2 (Microsoft) Fixed in 10.0.26300.9711
- Fix · CNA Windows Server 2012 (Microsoft) Fixed in 6.2.9200.26434
- Fix · CNA Windows Server 2012 (Server Core installation) (Microsoft) Fixed in 6.2.9200.26434
- Fix · CNA Windows Server 2012 R2 (Microsoft) Fixed in 6.3.9600.23470
- Fix · CNA Windows Server 2012 R2 (Server Core installation) (Microsoft) Fixed in 6.3.9600.23470
- Fix · CNA Windows Server 2016 (Microsoft) Fixed in 10.0.14393.9612
- Fix · CNA Windows Server 2016 (Server Core installation) (Microsoft) Fixed in 10.0.14393.9612
- Fix · CNA Windows Server 2019 (Microsoft) Fixed in 10.0.17763.9376
- Fix · CNA Windows Server 2019 (Server Core installation) (Microsoft) Fixed in 10.0.17763.9376
- Fix · CNA Windows Server 2022 (Microsoft) Fixed in 10.0.20348.5761
- Fix · CNA Windows Server 2025 (Microsoft) Fixed in 10.0.26100.33650
- Fix · CNA Windows Server 2025 (Server Core installation) (Microsoft) Fixed in 10.0.26100.33650
Timeline
- 2026-10-13 Threatist record created from CVE-2026-70096
- 2026-10-13 Alias added: GHSA-4wmg-p3q7-xrh2
- 2026-10-13 CISA SSVC decision points changed
- 2026-10-16 Fix available: Microsoft/Microsoft Office 365 for [email protected], Microsoft/Microsoft Office LTSC for Mac [email protected], Microsoft/Microsoft Office LTSC for Mac [email protected] · CNA
- 2026-10-16 Fix available: Microsoft/Windows 10 Version [email protected] · CNA
References
More Microsoft vulnerabilities
- TI-2026-42212 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2026-37256 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2026-26194 Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2026-16982 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2025-36863 Windows Server Update Service (WSUS) Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2025-33671 Microsoft SharePoint Server Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
Sources
- CVE-2026-70096 · CVE Program
- CVE-2026-70096 · NVD
- FIRST EPSS
- GHSA-4wmg-p3q7-xrh2 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences