CVE-2026-61347 in Windows
Summary
by MITRE • 08/11/2026
Buffer over-read in Windows Event Logging Service allows an authorized attacker to disclose information locally.
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Analysis
by VulDB Data Team • 08/11/2026
The vulnerability described represents a buffer over-read condition within the Windows Event Logging Service component that can be exploited by an authenticated local attacker to gain unauthorized information disclosure capabilities. This type of flaw occurs when the service processes event log data without proper bounds checking, allowing memory access beyond allocated buffer boundaries. The vulnerability falls under the category of improper input validation and memory safety issues commonly classified as CWE-125 - "Out-of-bounds Read" within the Common Weakness Enumeration framework. Such vulnerabilities are particularly concerning in system-level services like the Event Logging Service since they can expose sensitive system information that might otherwise remain protected.
The technical implementation of this flaw involves the Windows Event Logging Service handling event log entries that exceed expected buffer sizes during processing operations. When an attacker with local authenticated access crafts malicious event log data or manipulates existing log entries, the service fails to validate input lengths properly before copying data into fixed-size buffers. This results in memory being read beyond its intended boundaries, potentially exposing adjacent memory contents including sensitive data such as system credentials, application memory structures, or other confidential information stored in nearby memory locations. The attack vector requires local system access and authentication, making it a privilege escalation or information disclosure vulnerability rather than a remote exploit.
From an operational impact perspective, this vulnerability presents significant security implications for Windows environments where local access is possible. An attacker who has already gained user-level access to a system can leverage this flaw to extract potentially sensitive information from memory, which could then be used for further exploitation attempts including credential harvesting or system reconnaissance. The disclosed information might include process memory contents, stack data, or other system-related information that could aid in bypassing security controls or conducting more sophisticated attacks. This vulnerability particularly affects systems where event logging is actively used and where local attacker access exists through legitimate user accounts or compromised credentials.
Mitigation strategies for this vulnerability should focus on both immediate patching and operational security improvements. Microsoft has released security updates addressing this specific buffer over-read condition in the Event Logging Service, which should be deployed immediately across affected systems. Organizations should also implement monitoring for unusual event log processing patterns that might indicate exploitation attempts, particularly around memory access violations or malformed log entries. Additionally, implementing least privilege principles and restricting local system access can limit the potential impact of such vulnerabilities by reducing the number of potential attack vectors. The remediation aligns with ATT&CK technique T1059 - "Command and Scripting Interpreter" and T1068 - "Exploitation for Privilege Escalation" where unauthorized information disclosure can lead to further system compromise. Regular security assessments of system services and input validation mechanisms should be conducted to identify similar memory safety issues that might exist in other components of the Windows operating system stack.