EUVD-2026-56420
GHSA-632h-4gq8-hc2m
Severity by source
AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
AV:L reflects file-based delivery requiring local rendering; PR:N because no account privileges are needed; UI:R because victim must open the crafted document; full C/I/A impact confirmed by code execution outcome.
Primary rating from Vendor (microsoft).
CVSS VectorVendor: microsoft
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Lifecycle Timeline
3DescriptionCVE.org
Out-of-bounds read in Microsoft Office allows an unauthorized attacker to execute code locally.
AnalysisAI
Out-of-bounds read (CWE-125) in Microsoft Office enables local code execution across a broad range of Office product editions on both Windows and macOS. The CVSS vector (AV:L/AC:L/PR:N/UI:R) confirms the attack requires no privileges but does require a victim to open a crafted file, consistent with a malicious document delivery scenario. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | User interaction is required - the victim must actively open a specially crafted Office document, consistent with the UI:R CVSS metric. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 7.8 score reflects a high-severity local vulnerability with low attack complexity, no required privileges, and mandatory user interaction. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker crafts a malicious Office document that triggers the out-of-bounds read in the document parser when opened. The document is delivered to a target via spear-phishing email or a compromised file-sharing service. … |
| Remediation | Apply the vendor-released patch immediately. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours, complete inventory of all Microsoft Office installations across Windows and macOS endpoints and establish deployment priorities based on exposure risk, prioritizing administrators, executives, and business units handling external documents. …
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Same weakness CWE-125 – Out-of-bounds Read
View allSame technique Information Disclosure
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External POC / Exploit Code
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