EUVD-2026-56570
GHSA-w2q6-rm48-2h84
Severity by source
Sources disagree (Medium–Critical)AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Local vector and required user interaction confirmed by description; PR:N because no prior system privileges needed, only file delivery to user.
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 VectorNVD
Lifecycle Timeline
3DescriptionNVD
Out-of-bounds read in Microsoft Office Word allows an unauthorized attacker to disclose information locally.
AnalysisAI
Out-of-bounds read in Microsoft Office Word exposes sensitive memory contents to local attackers via crafted document files. Affected products span Word 2016 through Microsoft 365 Apps for Enterprise on both Windows and Mac platforms, covering a broad enterprise install base. Exploitation requires user interaction - a victim must open a malicious document - but yields high confidentiality impact with no integrity or availability loss. No public exploit has been identified at time of analysis.
Technical ContextAI
CWE-125 (Out-of-Bounds Read) describes a class of memory safety flaw where a parser or reader accesses memory beyond the boundary of an allocated buffer. In Microsoft Office Word, the vulnerable code path likely resides in the document parsing engine responsible for processing structured file formats such as .doc or .docx. When a specially crafted document triggers this path, the parser reads past the end of an intended buffer, potentially surfacing adjacent heap or stack contents - including pointers, cached credentials, or other in-memory data. The CVSS vector (AV:L/AC:L/PR:N/UI:R) confirms that no elevated privileges are needed by the attacker; only local execution context via user-opened file is required. Affected product families span Windows (Office 2019, LTSC 2021, LTSC 2024, Microsoft 365 Apps for Enterprise, Word 2016) and macOS (Office LTSC for Mac 2021 and 2024, Office 365 for Mac).
RemediationAI
Apply vendor-released patches immediately via Microsoft Update or the Office deployment tools. For Microsoft Word 2016 on Windows, update to version 16.0.5565.1000 or later. For all macOS Office variants (Office LTSC for Mac 2021, LTSC for Mac 2024, and Office 365 for Mac), update to version 16.112.26081010 or later. For Microsoft Office 2019, LTSC 2021, LTSC 2024, and Microsoft 365 Apps for Enterprise on Windows, apply updates as directed at https://aka.ms/OfficeSecurityReleases. The full vendor security advisory is available at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70310. As an interim compensating control where patching is not immediately feasible, organizations can configure Protected View policies via Group Policy to force all Word documents from external sources to open in read-only sandbox mode, which reduces but does not eliminate risk from malicious document delivery. Additionally, email gateway filtering to block or quarantine .doc/.docx attachments from untrusted senders can reduce the delivery surface; note this may impact legitimate document workflows.
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Same weakness CWE-125 – Out-of-bounds Read
View allSame technique Buffer Overflow
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External POC / Exploit Code
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