Microsoft disclosed and patched several remote code execution vulnerabilities affecting Microsoft Office, Excel, and Windows graphics components, including CVE-2026-42831, CVE-2026-26108, CVE-2025-49742, CVE-2024-49031, CVE-2024-49065, and CVE-2026-35421. The issues span Office document handling, Excel, the Office Graphics stack, the Windows Graphics Component, and Windows GDI, indicating broad exposure across common user-facing software used to process files and render content.
Microsoft said CVE-2026-42831 is a heap-based buffer overflow in Microsoft Office that can allow code execution when a user opens a malicious Office file. The flaw carries a CVSS 7.8 score, requires user interaction, and is not exploitable through the Preview Pane; Microsoft also said it was not publicly disclosed, not observed in the wild, and assessed as less likely to be exploited, with a security fix available. The related advisories point to a recurring risk pattern in which crafted documents or graphics content can trigger code execution on victim systems, reinforcing the need to prioritize patching for Office and Windows rendering components.

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Microsoft published CVE-2026-35421, a remote code execution vulnerability affecting Windows GDI.
Microsoft disclosed CVE-2026-42831, a critical heap-based buffer overflow in Microsoft Office that can lead to remote code execution if a user opens a malicious file. Microsoft said the flaw was not publicly disclosed, not exploited in the wild, exploitation was assessed as unlikely, and an official fix was available.
Microsoft published CVE-2026-26108, a remote code execution vulnerability affecting Microsoft Excel.
Microsoft published CVE-2025-49742, a remote code execution vulnerability in the Windows Graphics Component.
Microsoft published CVE-2024-49065, a remote code execution vulnerability affecting Microsoft Office.
Microsoft published CVE-2024-49031, a remote code execution vulnerability in Microsoft Office Graphics.
Microsoft published security guidance for CVE-2023-36423, a remote code execution vulnerability affecting the Microsoft Remote Registry Service.
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