CVE-2026-64914 in Access
Summary
by MITRE • 08/11/2026
Heap-based buffer overflow in Microsoft Office Access allows an unauthorized attacker to execute code locally.
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Analysis
by VulDB Data Team • 08/12/2026
A heap-based buffer overflow vulnerability exists in Microsoft Office Access that enables remote code execution by unauthorized attackers who can manipulate memory allocation patterns during application processing. This flaw occurs when the application fails to properly validate input data before writing to heap-allocated memory regions, allowing malicious actors to overwrite adjacent memory locations with crafted payload data. The vulnerability specifically affects the way Access handles certain database operations and file parsing functions that utilize dynamic memory allocation, creating opportunities for attackers to inject and execute arbitrary code within the context of the running application process.
The technical exploitation of this vulnerability leverages the fundamental principles of heap memory management where insufficient bounds checking permits buffer overflows to occur in dynamically allocated memory segments. Attackers can craft specially formatted database files or access objects that trigger the vulnerable code path, causing the application to write beyond allocated buffer boundaries into adjacent heap memory regions. This memory corruption can lead to overwrite critical data structures, function pointers, or return addresses, enabling attackers to redirect execution flow and ultimately achieve arbitrary code execution. The vulnerability demonstrates characteristics consistent with common weakness enumeration cwe-121 which identifies heap-based buffer overflow conditions as a primary attack vector for privilege escalation and remote code execution scenarios.
The operational impact of this vulnerability extends beyond simple local code execution as it provides attackers with persistent access to systems running vulnerable versions of Microsoft Office Access. Once successfully exploited, adversaries can establish backdoors, escalate privileges, and maintain long-term presence on compromised endpoints while potentially moving laterally through network infrastructure. The attack surface is particularly concerning given that Access applications are frequently used in business environments where users may encounter malicious database files through email attachments or shared network resources. This vulnerability creates opportunities for attackers to leverage the application's legitimate permissions and access patterns to bypass security controls and gain unauthorized access to sensitive organizational data.
Mitigation strategies should focus on immediate patch deployment from Microsoft as the primary defense mechanism against this heap-based buffer overflow vulnerability. Organizations must ensure all systems running Microsoft Office Access receive timely security updates and apply them across all endpoints to prevent exploitation attempts. Network segmentation and application whitelisting can provide additional protective layers by restricting access to vulnerable applications and limiting potential attack vectors. Security monitoring should include detection of suspicious file access patterns and memory allocation anomalies that may indicate exploitation attempts. Regular vulnerability assessments and penetration testing can help identify systems that may be running outdated versions or improperly configured Access installations that could remain susceptible to this class of heap overflow attacks. The remediation approach should also consider implementing principle of least privilege controls and restricting user permissions to prevent unauthorized database modifications that could facilitate exploitation.