Severity by source
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Local file-open trigger with no privileges needed, user must interact; confidentiality-only impact matches heap read disclosure with no write or crash path.
Primary rating from Vendor (microsoft).
CVSS VectorNVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Lifecycle Timeline
3DescriptionNVD
Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to disclose information locally.
AnalysisAI
Heap-based buffer overflow in Microsoft Office Word enables a local, unauthenticated attacker to disclose sensitive memory contents by enticing a user to open a maliciously crafted document. Affected products span Microsoft Word 2016, Microsoft 365 Apps for Enterprise, Office LTSC 2021/2024 on Windows, and Office LTSC/365 on macOS. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | Exploitation requires that a target user actively open a specially crafted Word document on a system running an affected version of Microsoft Office Word. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 5.5 (Medium) base score is consistent with the real-world risk profile here. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker crafts a malicious Word document containing parser-triggering content designed to overflow a heap buffer during file open, causing adjacent heap memory to be read and potentially exfiltrated through a document feature such as linked content or a macro callback. The attacker delivers this document via a phishing email, and a user with an unpatched Office installation opens it, triggering the information disclosure. … |
| Remediation | The primary fix is to apply Microsoft's released patch through the standard Office update mechanism. … Detailed patch versions, workarounds, and compensating controls in full report. |
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Same weakness CWE-122 – Heap-based Buffer Overflow
View allSame technique Heap Overflow
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External POC / Exploit Code
Leaving vuln.today
EUVD-2026-56751
GHSA-jjhm-qqfx-22xc