CVE-2026-55017
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk23th percentile - higher than 23% of all known CVEs
Summary
A heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally. The issue stems from improper memory management when processing specially crafted data.
Risk Assessment
An attacker can gain full control of the victim's system, leading to data theft, malware installation, or lateral movement within the network.
Recommendation
Apply the security update provided by Microsoft for the affected Office version immediately. Restrict execution of macros and documents from untrusted sources.
Other vulnerabilities in Microsoft Office
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Improper access control in Microsoft Office allows an unauthorized attacker to perform spoofing locally.
- CVE-2026-42831High
Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
- CVE-2026-40419High
A use after free vulnerability in Microsoft Office allows an authorized attacker to locally elevate privileges.
- CVE-2026-40363High
Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
- CVE-2026-26134High
Integer overflow or wraparound in Microsoft Office allows an authorized attacker to elevate privileges locally.
- CVE-2026-26110High
Microsoft Office has a vulnerability related to resource access using an incompatible type ('type confusion'), allowing an unauthorized attacker to execute code locally.
- CVE-2026-20953High
Use after free in Microsoft Office allows an unauthorized attacker to execute code locally.
- CVE-2026-20952High
Use after free in Microsoft Office allows an unauthorized attacker to execute code locally.
- CVE-2026-20943High
An untrusted search path vulnerability in Microsoft Office allows an unauthorized attacker to execute code locally.
- CVE-2025-62557High
A use after free vulnerability in Microsoft Office allows an unauthorized attacker to execute code locally.
Original NVD description (English source)
Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.