Quick answers
- Is CVE-2026-55033 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-55033 being exploited in the wild.
- How severe is CVE-2026-55033?
- High severity, with a CVSS score of 7.8, published 14 July 2026.
- Which products and versions are affected?
- Microsoft Word Microsoft 365 Apps, Office 2019, Office LTSC 2021/2024, Office for Mac, SharePoint Server.
- Is there a fix for CVE-2026-55033?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-55033 attacked?
- It is attacked with local access, in a network appliance.
- Am I affected by CVE-2026-55033?
- Check whether you run Microsoft SharePoint Server or Microsoft Word at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
An integer overflow or wraparound vulnerability (CWE-190) exists in Microsoft Office Word, which can lead to a heap-based buffer overflow (CWE-122). The vulnerability is triggered when the application processes a specially crafted document. While the attack vector is local, it requires user interaction (UI:R), typically involving a victim opening a malicious file provided by the attacker. Successful exploitation allows for arbitrary code execution in the context of the current user. Microsoft has released security updates to address this issue across various versions of Office and SharePoint Server.
Affected products
- Microsoft Office Word Microsoft 365 Apps, Office 2019, Office LTSC 2021/2024, Office for Mac, SharePoint Server
Timeline
- 2026-07-14: disclosed
- 2026-07-14: advisory