Office Long Term Servicing Channel
CVE-2026-20946
HIGH
Severity by source
AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Primary rating from NVD.
CVSS VectorNVD
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Lifecycle Timeline
2DescriptionCVE.org
Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
AnalysisAI
Local code execution in Microsoft Office Excel occurs through an out-of-bounds memory read vulnerability affecting the Long Term Servicing Channel, Office 365 Apps, and standalone Office installations. An attacker with local access and user interaction can exploit this flaw to achieve arbitrary code execution with full system privileges. No patch is currently available for this high-severity vulnerability.
Technical ContextAI
Classified as CWE-125 (Out-of-bounds Read). Affects 365 Apps. Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
RemediationAI
Monitor vendor advisories for a patch.
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Same weakness CWE-125 – Out-of-bounds Read
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External POC / Exploit Code
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