Microsoft Excel Remote Code Execution Vulnerability
Priority LOW 37CWE-122Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- None
- User interaction
- Required
- 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 and Microsoft. Impact type from Microsoft.
Summary
Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00553 46th percentileScored 2026-11-07
Fix Fixed Microsoft: 3 updates
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- 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 Excel 2016 | 16.0.0.0 to before 16.0.5543.1000 | 16.0.5543.1000 | Patch available | CNA |
| Microsoft | Microsoft Office 2019 | 19.0.0 to before https://aka.ms/OfficeSecurityReleases | https://aka.ms/OfficeSecurityReleases | Patch available | CNA |
| Microsoft | Microsoft Office LTSC 2021 | 16.0.1 to before https://aka.ms/OfficeSecurityReleases | https://aka.ms/OfficeSecurityReleases | Patch available | CNA |
| Microsoft | Microsoft Office LTSC 2024 | 16.0.0 to before https://aka.ms/OfficeSecurityReleases | https://aka.ms/OfficeSecurityReleases | Patch available | CNA |
| Microsoft | Microsoft Office LTSC for Mac 2021 | 16.0.1 to before 16.107.26030819 | 16.107.26030819 | Patch available | CNA |
| Microsoft | Microsoft Office LTSC for Mac 2024 | 16.0.0 to before 16.107.26030819 | 16.107.26030819 | Patch available | CNA |
| Microsoft | Office Online Server | 16.0.0.0 to before 16.0.10417.20102 | 16.0.10417.20102 | 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 Excel 2016 VendorMicrosoft Affected 16.0.0.0 to before 16.0.5543.1000 Fixed in 16.0.5543.1000 Patch available CNA
- Microsoft Office 2019 VendorMicrosoft Affected 19.0.0 to before https://aka.ms/OfficeSecurityReleases Fixed in https://aka.ms/OfficeSecurityReleases Patch available CNA
- Microsoft Office LTSC 2021 VendorMicrosoft Affected 16.0.1 to before https://aka.ms/OfficeSecurityReleases Fixed in https://aka.ms/OfficeSecurityReleases Patch available CNA
- Microsoft Office LTSC 2024 VendorMicrosoft Affected 16.0.0 to before https://aka.ms/OfficeSecurityReleases Fixed in https://aka.ms/OfficeSecurityReleases Patch available CNA
- Microsoft Office LTSC for Mac 2021 VendorMicrosoft Affected 16.0.1 to before 16.107.26030819 Fixed in 16.107.26030819 Patch available CNA
- Microsoft Office LTSC for Mac 2024 VendorMicrosoft Affected 16.0.0 to before 16.107.26030819 Fixed in 16.107.26030819 Patch available CNA
- Office Online Server VendorMicrosoft Affected 16.0.0.0 to before 16.0.10417.20102 Fixed in 16.0.10417.20102 Patch available CNA
CPE configurations NVD · 14
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:* | not specified by NVD | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:* | not specified by NVD | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:excel:2016:*:*:*:*:*:x64:* | 2016 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:excel:2016:*:*:*:*:*:x86:* | 2016 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:x64:* | 2019 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:x86:* | 2019 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x64:* | 2021 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x86:* | 2021 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:macos:*:* | 2021 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x64:* | 2024 | Vulnerable | Microsoft |
- cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:* Versions not specified by NVD Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:* Versions not specified by NVD Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:excel:2016:*:*:*:*:*:x64:* Versions 2016 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:excel:2016:*:*:*:*:*:x86:* Versions 2016 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:x64:* Versions 2019 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:x86:* Versions 2019 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x64:* Versions 2021 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x86:* Versions 2021 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:macos:*:* Versions 2021 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x64:* Versions 2024 Vulnerable ·Microsoft
Show 4 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x86:* | 2024 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:macos:*:* | 2024 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:office_online_server:*:*:*:*:*:*:*:* | before 16.0.10417.20102 | Vulnerable | Microsoft |
| cpe:2.3:a:microsoft:office_online_server:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | Microsoft |
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x86:* Versions 2024 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:macos:*:* Versions 2024 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:office_online_server:*:*:*:*:*:*:*:* Versions before 16.0.10417.20102 Vulnerable ·Microsoft
- cpe:2.3:a:microsoft:office_online_server:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Microsoft
Remediation
Microsoft 3 updates
- Security Update
- Microsoft Excel 2016 (32-bit edition) 16.0.5543.1000
- Microsoft Excel 2016 (64-bit edition) 16.0.5543.1000
- Security Update
- Office Online Server 16.0.10417.20102, 16.0.10417.20113
- Security Update
- Microsoft Excel 2016 (32-bit edition) 16.0.5543.1000
- Microsoft Excel 2016 (64-bit edition) 16.0.5543.1000
Vendor assessments
Microsoft
Microsoft's page for this CVE →
- Impact
- Remote Code Execution
- Exploited
- No
- Publicly disclosed
- No
- Exploitability
- Exploitation Less Likely
| Product | Status | Plan or fix |
|---|---|---|
| Microsoft 365 Apps for Enterprise for 32-bit Systems | Fixed | https · //aka.ms/OfficeSecurityReleases |
| Microsoft 365 Apps for Enterprise for 64-bit Systems | Fixed | https · //aka.ms/OfficeSecurityReleases |
| Microsoft Office 2019 for 32-bit editions | Fixed | https · //aka.ms/OfficeSecurityReleases |
| Microsoft Office 2019 for 64-bit editions | Fixed | https · //aka.ms/OfficeSecurityReleases |
| Microsoft Office LTSC 2021 for 32-bit editions | Fixed | https · //aka.ms/OfficeSecurityReleases |
| Microsoft Office LTSC 2021 for 64-bit editions | Fixed | https · //aka.ms/OfficeSecurityReleases |
| Microsoft Office LTSC 2024 for 32-bit editions | Fixed | https · //aka.ms/OfficeSecurityReleases |
| Microsoft Office LTSC 2024 for 64-bit editions | Fixed | https · //aka.ms/OfficeSecurityReleases |
| Microsoft Office LTSC for Mac 2021 | Fixed | 16.107.26030819 · Security Update |
| Microsoft Office LTSC for Mac 2024 | Fixed | 16.107.26030819 · Security Update |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-26108
- 2026-10-03 Alias added: GHSA-592m-3g3c-6r9c
References
More Microsoft 365 Apps vulnerabilities
- TI-2024-14173 Microsoft Outlook Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2023-09240 Microsoft Outlook Elevation of Privilege Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2024-25471 Microsoft Project Remote Code Execution Vulnerability KEVCVSS 3.1HIGH 8.8
- TI-2023-17652 Microsoft Outlook Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 8.8
- TI-2026-17368 Microsoft Word Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 7.8
- TI-2026-17363 Microsoft Office Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 7.8
Sources
- CVE-2026-26108 · CVE Program
- CVE-2026-26108 · NVD
- FIRST EPSS
- GHSA-592m-3g3c-6r9c · GitHub Advisory Database · CC BY 4.0
- CVE-2026-26108 · Microsoft Security Update Guide
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences