Microsoft Security Update Guide · Office / Microsoft 365 Apps
Microsoft Word Remote Code Execution Vulnerability
Published
What does this mean?
- Remote Code Execution. An attacker can run their own code on the system remotely. This is the most serious type: it can lead to taking over the system.
- It can be exploited with access to the device itself, without an account and if a user takes part, for example by opening a link or file.
- CVSS 7.8 out of 10: high. Microsoft rates it Important.
- No attacks reported; Microsoft expects exploitation to be less likely.
- What should you do? Install the security update for the version you run (or a later cumulative update):
- Microsoft Office 365 for Mac: KBRelease Notes
16.111.26071215 - Microsoft Word 2016 (64-bit edition): KB5002890
16.0.5561.1000 - Microsoft Word 2016 (32-bit edition): KB5002890
16.0.5561.1000 - Microsoft Office LTSC for Mac 2024: KBRelease Notes
16.111.26071215 - Microsoft Office LTSC 2024 for 64-bit editions: KBClick to Run
https://aka.ms/OfficeSecurityReleases - Microsoft Office LTSC 2024 for 32-bit editions: KBClick to Run
https://aka.ms/OfficeSecurityReleases
- Microsoft Office 365 for Mac: KBRelease Notes
Stack-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code locally.
How do I check if I am affected?
SharePoint Server: check and update
- Check your farm build in the SharePoint Management Shell:
Or in Central Administration → Upgrade and Migration → Check product and patch installation status.(Get-SPFarm).BuildVersion - If the build is equal to or higher than the build under "Affected products and updates" below, this vulnerability is fixed. A later cumulative update includes the fix too.
- Otherwise install the update on every server in the farm, then run the SharePoint Products Configuration Wizard, or:
PSConfig.exe -cmd upgrade -inplace b2b -wait -cmd applicationcontent -install -cmd installfeatures -cmd secureresources -cmd services -install - You do not need to update SharePoint Online in Microsoft 365; Microsoft does that.
Key facts
Released
14 jul 2026
Impact
Remote Code Execution
Max severity
Important
Weakness
CVSS 3.1
7.8 / 6.8 (base / temporal)
Vector string
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:CPublicly disclosed
No
Exploited
No
Exploitability assessment
Exploitation Less Likely
Customer action required
Yes
Links
CVSS metrics
| Base score metrics | |
|---|---|
| Attack Vector | Local |
| Attack Complexity | Low |
| Privileges Required | None |
| User Interaction | Required |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity | High |
| Availability | High |
| Temporal score metrics | |
| Exploit Code Maturity | Unproven |
| Remediation Level | Official Fix |
| Report Confidence | Confirmed |
Affected products and updates
| Product | Update | Build |
|---|---|---|
| Microsoft Office 365 for Mac | KBRelease Notes · Security Update | 16.111.26071215 |
| Microsoft Word 2016 (64-bit edition) | KB5002890 · Security Update | 16.0.5561.1000 |
| Microsoft Word 2016 (32-bit edition) | KB5002890 · Security Update | 16.0.5561.1000 |
| Microsoft Office LTSC for Mac 2024 | KBRelease Notes · Security Update | 16.111.26071215 |
| Microsoft Office LTSC 2024 for 64-bit editions | KBClick to Run | https://aka.ms/OfficeSecurityReleases |
| Microsoft Office LTSC 2024 for 32-bit editions | KBClick to Run | https://aka.ms/OfficeSecurityReleases |
| Microsoft SharePoint Server Subscription Edition | KB5002882 · Security Update | 16.0.19725.20434 |
| Microsoft Office LTSC 2021 for 32-bit editions | KBClick to Run | https://aka.ms/OfficeSecurityReleases |
| Microsoft Office LTSC 2021 for 64-bit editions | KBClick to Run | https://aka.ms/OfficeSecurityReleases |
| Microsoft Office LTSC for Mac 2021 | KBRelease Notes · Security Update | 16.111.26071215 |
| Microsoft 365 Apps for Enterprise for 64-bit Systems | KBClick to Run | https://aka.ms/OfficeSecurityReleases |
| Microsoft 365 Apps for Enterprise for 32-bit Systems | KBClick to Run | https://aka.ms/OfficeSecurityReleases |
| Microsoft Office 2019 for 64-bit editions | KBClick to Run | https://aka.ms/OfficeSecurityReleases |
| Microsoft Office 2019 for 32-bit editions | KBClick to Run | https://aka.ms/OfficeSecurityReleases |
| Microsoft SharePoint Server 2019 | KB5002883 · Security Update | 16.0.10417.20175 |
| Microsoft SharePoint Server 2019 | KB5002885 · Security Update | 16.0.10417.20175 |
| Microsoft SharePoint Enterprise Server 2016 | KB5002891 · Security Update | 16.0.5561.1001 |
| Microsoft SharePoint Enterprise Server 2016 | KB5002892 · Security Update | 16.0.5561.1001 |
FAQ
- According to the CVSS metric, the attack vector is local (AV:L). Why does the CVE title indicate that this is a remote code execution?
- The word Remote in the title refers to the location of the attacker. This type of exploit is sometimes referred to as Arbitrary Code Execution (ACE). The attack itself is carried out locally. This means an attacker or victim needs to execute code from the local machine to exploit the vulnerability.
- Is the Preview Pane an attack vector for this vulnerability?
- No, the Preview Pane is not an attack vector.
- There are multiple update packages available for some of the affected software. Do I need to install all the updates listed in the Security Updates table for the software?
- Yes. Customers should apply all updates offered for the software installed on their systems. If multiple updates apply, they can be installed in any order.
- According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do?
- An attacker must send a user a malicious Office file and convince them to open it.
Revisions
| Version | Date | Note |
|---|---|---|
| 1 | 14 jul 2026 | Information published. |
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Source: Microsoft Security Update Guide. 365Fanatic is not affiliated with Microsoft.
