CVE-2026-55056
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk27th percentile - higher than 27% of all known CVEs
Summary
A heap-based buffer overflow vulnerability in Microsoft Office allows an unauthorized attacker to execute code locally. The issue stems from improper memory management when processing specially crafted files.
Risk Assessment
An attacker could gain full control of the victim's system, installing malware, modifying data, or taking over user privileges.
Recommendation
Immediately install the security update provided by Microsoft for the affected Office version. Restrict opening files 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.