EUVD-2026-56578
GHSA-mgjf-xg67-j2cr
Severity by source
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Local vector because disclosed data is only retrievable in local context; PR:N since crafting the malicious document requires no system privileges; UI:R as the victim must open the file; C:H for meaningful information disclosure with no integrity or availability impact.
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
Improper input validation in Microsoft Office Word allows an unauthorized attacker to disclose information locally.
AnalysisAI
Microsoft Office Word's document parsing logic fails to properly validate input (CWE-20), enabling a local attacker to read sensitive information from a target system when a victim opens a specially crafted Word document. The flaw affects a broad range of Microsoft Office releases on both Windows and macOS, including Microsoft 365 Apps for Enterprise, Office 2019, and all LTSC variants through 2024. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | Exploitation requires the victim to actively open a specially crafted Word document (UI:R per CVSS vector) - this is the sole triggering condition and a hard prerequisite. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 3.1 score of 5.5 (Medium) is internally consistent: the local attack vector (AV:L) and required user interaction (UI:R) significantly constrain mass exploitation, while the High confidentiality impact (C:H) reflects the potential for meaningful data disclosure when triggered. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker crafts a malicious Word document embedding malformed input designed to bypass Word's validation logic, then delivers it to a target via phishing email or shared network storage. When the victim opens the document on their local machine, the flawed parsing code reads and exposes sensitive local data - such as file contents or memory regions accessible to the Word process - which the attacker can retrieve if they have local access or have instrumented a secondary exfiltration channel. … |
| Remediation | Apply the vendor-released patch immediately via standard Microsoft update channels. … Detailed patch versions, workarounds, and compensating controls in full report. |
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Same weakness CWE-20 – Improper Input Validation
View allSame technique Information Disclosure
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External POC / Exploit Code
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