EUVD-2026-56421
GHSA-qcgw-c39h-2v8h
Severity by source
AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Local vector because exploitation requires the victim to open a crafted file; no integrity or availability impact since only adjacent memory is read.
Primary rating from Vendor (microsoft).
CVSS VectorVendor: microsoft
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Lifecycle Timeline
3DescriptionCVE.org
Out-of-bounds read in Microsoft Office allows an unauthorized attacker to disclose information locally.
AnalysisAI
Out-of-bounds read in Microsoft Office exposes sensitive in-process memory contents to local attackers who socially engineer a victim into opening a crafted document. The flaw spans the full Microsoft Office portfolio across Windows and macOS - from Office 2016 through Microsoft 365 Apps for Enterprise - making it broadly relevant for enterprise patch management. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | The victim must actively open a specially crafted Office document on an affected installation - user interaction is mandatory (UI:R per CVSS). … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 3.1 base score of 5.5 (Medium) accurately reflects the constrained attack surface: local-only vector (AV:L), mandatory user interaction (UI:R), and impact limited to confidentiality (C:H/I:N/A:N). … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker crafts a malicious Office document engineered to trigger an out-of-bounds read during file parsing and delivers it to a target via phishing email or a drive-by download. When the victim opens the file on an affected Office installation, the parser reads beyond the intended buffer and adjacent memory contents - potentially including sensitive in-process data or address-space layout information - are exposed. … |
| Remediation | The definitive fix is to apply Microsoft's released patch. … Detailed patch versions, workarounds, and compensating controls in full report. |
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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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