CVE-2021-34522
HighCVSS 7.8Exploitation Probability (EPSS)
High risk84th percentile - higher than 84% of all known CVEs
Summary
A vulnerability in Microsoft Defender allows remote code execution (RCE).
Risk Assessment
An attacker could exploit the vulnerability to execute code in the context of Defender, potentially leading to privilege escalation.
Recommendation
Install the latest Microsoft Defender updates.
Other vulnerabilities in Microsoft Defender
See all- CVE-2026-45498MediumActively exploited
Microsoft Defender Denial of Service Vulnerability.
- CVE-2026-41091HighActively exploited
Improper link resolution before file access ('link following') in Microsoft Defender allows an authorized attacker to elevate privileges locally.
- CVE-2026-33825HighActively exploited
Insufficient granularity of access control in Microsoft Defender allows an authorized attacker to elevate privileges locally.
- CVE-2021-42298High
Remote code execution vulnerability in Microsoft Defender. An attacker could exploit this vulnerability to execute arbitrary code on the system.
- CVE-2026-50658High
A Time-of-check time-of-use (TOCTOU) race condition in Microsoft Defender allows an authorized attacker to elevate privileges locally.
- CVE-2026-50657Medium
In Microsoft Defender, exposure of private personal information to an unauthorized actor allows an authorized attacker to disclose information locally.
- CVE-2026-55012High
An integer overflow or wraparound vulnerability has been discovered in Microsoft Defender. This flaw allows an unauthorized attacker to execute code locally.
- CVE-2026-55011High
An integer underflow (wrap or wraparound) vulnerability in Microsoft Defender allows an unauthorized attacker to execute code locally.
- CVE-2026-45584High
Heap-based buffer overflow in Microsoft Defender allows an unauthorized attacker to execute code over a network.
- CVE-2023-33156Medium
A vulnerability in Microsoft Defender allows for elevation of privilege, potentially leading to unauthorized access to the system.
Original NVD description (English source)
Microsoft Defender Remote Code Execution Vulnerability