CVE-2026-56156
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk26th percentile - higher than 26% of all known CVEs
Summary
A heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
Risk Assessment
An attacker could exploit this vulnerability to take control of the victim's system, leading to data theft or malware installation.
Recommendation
Apply the security update provided by Microsoft for Excel immediately.
Other vulnerabilities in Microsoft Office Excel
See all- CVE-2026-40360High
An out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to disclose information locally.
- CVE-2026-40359High
A use after free vulnerability in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
- CVE-2026-20957High
Integer underflow (wrap or wraparound) in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
- CVE-2026-20956High
Untrusted pointer dereference in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
- CVE-2026-20955High
Untrusted pointer dereference in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
- CVE-2026-20950High
Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
- CVE-2026-20949High
Improper access control in Microsoft Office Excel allows an unauthorized attacker to bypass a security feature locally.
- CVE-2026-20946High
An out-of-bounds read vulnerability in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
- CVE-2026-70328Medium
Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to disclose information over a network.
- CVE-2026-70327Medium
Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to disclose information over a network.
Original NVD description (English source)
Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.