Severity by source
Sources disagree (Low–High)AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
vuln.today treats the vendor’s rating as authoritative. A higher third-party CVSS (e.g. CISA-ADP) is shown for transparency but does not drive the headline severity.
CVSS VectorVendor: microsoft
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Lifecycle Timeline
1DescriptionCVE.org
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 exposes limited local memory contents when a user opens a specially crafted document. Affecting multiple Office product lines including Microsoft 365 Apps for Enterprise, Office LTSC 2021, LTSC 2024, and their Mac counterparts, the vulnerability carries a CVSS score of 3.3 (Low) and is constrained to confidentiality impact only, with no integrity or availability consequences. No public exploit code has been identified at time of analysis, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.
Technical ContextAI
The root cause is CWE-122 (Heap-based Buffer Overflow), a memory safety defect in which Word's document parsing logic writes beyond the bounds of a heap-allocated buffer. This class of vulnerability arises when input length validation fails before a memory copy or write operation targeting a heap region, potentially exposing adjacent heap memory to a read-based disclosure. The CVSS vector (AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N) indicates the overflow is reachable locally with low complexity, requiring only that a user open a malicious file, and that the scope of impact is unchanged - meaning exploitation is confined to the Word process itself. Affected product lines span Windows and macOS deployments: Microsoft 365 Apps for Enterprise (build 16.0.1 and prior), Microsoft Office LTSC 2024 (build 16.0.0 and prior), Microsoft Office LTSC 2021 (build 16.0.1 and prior), and the corresponding Mac variants (Office 365 for Mac, Office LTSC for Mac 2024, Office LTSC for Mac 2021).
RemediationAI
The primary remediation is to apply the vendor-released patch via Microsoft Update or the Office update mechanism. For Windows-based deployments, update Microsoft 365 Apps for Enterprise to build 16.0.1 or later, Microsoft Office LTSC 2024 to the build specified at https://aka.ms/OfficeSecurityReleases, and Microsoft Office LTSC 2021 to build 16.0.1 or later. For Mac deployments across Office 365 for Mac, LTSC for Mac 2024, and LTSC for Mac 2021, apply the latest available update as specific fixed build numbers were not enumerated in source data - consult https://aka.ms/OfficeSecurityReleases directly for current Mac build guidance. As a compensating control where immediate patching is not feasible, organizations can configure Protected View to open all externally sourced documents in read-only sandboxed mode, which limits the attack surface by reducing the document processing code paths reachable before user promotion. Note that Protected View does not eliminate the vulnerability; it reduces exposure by adding a user confirmation step before full document rendering. No workarounds that fully mitigate the vulnerability without patching have been identified in the source data.
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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-2026-35672
GHSA-pjqr-gm8f-m9wv