CVE-2026-55123
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedHeap-based buffer overflow in Microsoft Office PowerPoint allows an unauthorized attacker to execute code locally.
In the news
Third-party coverage- Microsoft July 2026 Patch Tuesday fixes massive 570 flaws, 3 zero-days
- Microsoft CVE Summary - Bleeping Computer
Surfaced from public web coverage — external links open in a new tab.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceA heap-based buffer overflow vulnerability in Microsoft Office PowerPoint allows an unauthorized attacker to execute arbitrary code locally by crafting a malicious PowerPoint file.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE dataall versionsall versionsall versionsall versionsall versions= 2016CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Verify PowerPoint installationCheck for the presence of POWERPNT.EXE in typical Office installation paths such as C:\Program Files\Microsoft Office\root\Office##\POWERPNT.EXE or C:\Program Files (x86)\Microsoft Office\Office##\POWERPNT.EXE, or locate via Start menu searchAffected if PowerPoint executable is found on the system
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Identify installed PowerPoint versionRight-click POWERPNT.EXE, select Properties, then go to the Details tab to read the Product version field, or use Command 'dir POWERPNT.EXE /s' to locate the file and check its version propertiesAffected if The product version displayed is 2016 or matches any version of Office 2019, Office 2021, Office 2024, or Microsoft 365 Apps
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Check Office subscription or license versionOpen any Office application, go to File > Account or File > Account Settings > About to view the installed version and update channel informationAffected if The Office installation shows as Microsoft 365 Apps, Office 2019, Office 2021, or Office 2024 with any version number
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Confirm PowerPoint is the vulnerable componentSince this CVE specifically targets PowerPoint, verify that PowerPoint is the component listed as affected rather than other Office applicationsAffected if PowerPoint is installed and the version matches affected Office product lines
The environment is affected if Microsoft PowerPoint is installed with version 2016, or as part of Microsoft Office 2019, 2021, 2024, or Microsoft 365 Apps any version, as all these versions are listed as vulnerable to this heap-based buffer overflow.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataApply Microsoft security updates for Office or upgrade to a patched version of Microsoft Office to remediate this vulnerability.
- Consultation3.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,168.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-55123 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-55123 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data