Microsoft Office Online Server vulnerabilities

CVE-2025-59223 [HIGH] CWE-416 CVE-2025-59223: Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally. Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2026-55141 [HIGH] CWE-121 CVE-2026-55141: Stack-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute cod Stack-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2026-55899 [HIGH] CWE-20 CVE-2026-55899: Stack-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute cod Stack-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2025-27746 [HIGH] CWE-416 CVE-2025-27746: Use after free in Microsoft Office allows an unauthorized attacker to execute code locally. Use after free in Microsoft Office allows an unauthorized attacker to execute code locally.

CVE-2025-53735 [HIGH] CWE-416 CVE-2025-53735: Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally. Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2025-53737 [HIGH] CWE-122 CVE-2025-53737: Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2025-53741 [HIGH] CWE-122 CVE-2025-53741: Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2026-26109 [HIGH] CWE-125 CVE-2026-26109: Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to execute code locally Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2026-55048 [HIGH] CWE-122 CVE-2026-55048: Integer overflow or wraparound in Microsoft Office Excel allows an unauthorized attacker to execute Integer overflow or wraparound in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2026-55039 [HIGH] CWE-122 CVE-2026-55039: Integer underflow (wrap or wraparound) in Microsoft Office Excel allows an unauthorized attacker to Integer underflow (wrap or wraparound) in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2026-55949 [HIGH] CWE-908 CVE-2026-55949: Use of uninitialized resource in Microsoft Office Excel allows an unauthorized attacker to execute c Use of uninitialized resource in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2020-16932 [HIGH] CWE-908 CVE-2020-16932: <p>A remote code execution vulnerability exists in Microsoft Excel software when the software fails A remote code execution vulnerability exists in Microsoft Excel software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker could take control of t

CVE-2020-16931 [HIGH] CWE-908 CVE-2020-16931: <p>A remote code execution vulnerability exists in Microsoft Excel software when the software fails A remote code execution vulnerability exists in Microsoft Excel software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker could take control of t

CVE-2020-16929 [HIGH] CWE-416 CVE-2020-16929: <p>A remote code execution vulnerability exists in Microsoft Excel software when the software fails A remote code execution vulnerability exists in Microsoft Excel software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker could take control of t

CVE-2025-24082 [HIGH] CWE-416 CVE-2025-24082: Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally. Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2025-24081 [HIGH] CWE-416 CVE-2025-24081: Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally. Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2025-60727 [HIGH] CWE-125 CVE-2025-60727: Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to execute code locally Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2026-20955 [HIGH] CWE-822 CVE-2026-20955: Untrusted pointer dereference in Microsoft Office Excel allows an unauthorized attacker to execute c Untrusted pointer dereference in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2025-29979 [HIGH] CWE-122 CVE-2025-29979: Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVE-2025-29977 [HIGH] CWE-416 CVE-2025-29977: Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally. Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.