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Microsoft disclosed CVE-2026-62870, a high-severity remote code execution vulnerability in Microsoft Excel caused by a use-after-free flaw. The bug carries a CVSS v3.1 score of 8.8 and affects Microsoft 365 Apps for Enterprise, Excel 2016, Office 2019, Office LTSC 2021, and Office LTSC 2024 on both 32-bit and x64-based systems. According to the advisory, an unauthenticated attacker could exploit the flaw over a network by delivering a specially crafted Excel file and executing code in the context of the current user.
Microsoft released security updates addressing the issue, and reporting indicates exploitation requires user interaction to open the malicious file. Successful compromise could let attackers install malware, steal data, and pivot further into enterprise environments depending on the victim's privileges. At the time of publication, there was no public exploit and no confirmed active exploitation, and the vulnerability had not been added to CISA's Known Exploited Vulnerabilities catalog.
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4 events from the most recent confirmed update back to the earliest known activity.
The Excel use-after-free remote code execution vulnerability CVE-2026-62870 was publicly disclosed. At the time of publication, the reporting stated there was no confirmed public exploit, no confirmed active exploitation, and the flaw had not been added to CISA's Known Exploited Vulnerabilities catalog.
The CVE entry for CVE-2026-62870 was published with Microsoft as the source, documenting the flaw as a use-after-free vulnerability in Microsoft Office Excel that allows unauthorized code execution over a network. The entry included affected products, CVSS data, CWE-416 mapping, and a reference to Microsoft's Security Response Center advisory.
The vulnerability CVE-2026-62870 was published in the National Vulnerability Database as a high-severity Microsoft Excel remote code execution issue caused by a use-after-free weakness.
Microsoft released security updates to address CVE-2026-62870, a high-severity use-after-free remote code execution flaw in Excel affecting multiple Office product lines. The updates are described as the only complete fix for the vulnerability.
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Microsoft published security advisories for several **remote code execution** vulnerabilities affecting **Microsoft Office** and **Microsoft Excel**, including `CVE-2025-24057`, `CVE-2025-24075`, and `CVE-2025-47162`. The issues were listed in the Microsoft Security Update Guide as Office-family flaws that could allow arbitrary code execution if successfully exploited. The disclosures indicate that the affected attack surface spans both the broader Office suite and Excel specifically, underscoring continued risk from malicious documents and content processed by productivity software. Organizations using Microsoft Office should prioritize review of the relevant advisories and deployment of associated security updates for the affected products tied to these CVEs.
Jul 12, 2026
Microsoft published a long series of security advisories for **remote code execution** vulnerabilities affecting core Office components, with the largest concentration in **Excel** and **Word**. The disclosures include Excel flaws such as `CVE-2024-49026`, `CVE-2024-49069`, `CVE-2025-21362`, `CVE-2025-21381`, `CVE-2025-21387`, `CVE-2025-24082`, `CVE-2025-62553`, `CVE-2026-26107`, `CVE-2026-26109`, `CVE-2026-26112`, and `CVE-2026-40359`, alongside Word issues including `CVE-2025-24077`, `CVE-2025-24078`, `CVE-2025-47170`, `CVE-2025-49700`, `CVE-2025-59222`, `CVE-2026-23657`, and `CVE-2026-33095`. Microsoft also listed related RCE bugs in **Microsoft Office** (`CVE-2025-21392`), **PowerPoint** (`CVE-2025-54908`), **Inbox COM Objects (Global Memory)** (`CVE-2025-58730`), and the **Visual Studio Code Python Extension** (`CVE-2025-49714`). One of the few entries with technical detail, **`CVE-2026-40359`**, describes an **Important** Excel use-after-free flaw (`CWE-416`) with a **CVSS 3.1 score of 7.8** that can let an attacker execute code if a user opens a malicious Office file. Microsoft said the bug was **not publicly disclosed**, **not exploited in the wild**, and **less likely** to be exploited at the time of publication, adding that the **Preview Pane is not an attack vector** and that a fix is available. Taken together, the advisories show Microsoft continuing to address document-driven code execution risks across Office products, where successful exploitation generally depends on **user interaction with crafted files** rather than direct network exposure.
Jun 29, 2026
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.
Jun 29, 2026