CVE-2026-96245 in Windows
Summary
by MITRE • 10/14/2026
Out-of-bounds read in Windows Routing and Remote Access Service (RRAS) allows an unauthorized attacker to disclose information over a network.
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Analysis
by VulDB Data Team • 10/14/2026
The vulnerability identified as an out-of-bounds read within the Microsoft Windows Routing and Remote Access Service, commonly referred to as RRAS, represents a critical memory safety flaw that compromises the integrity of system data during network packet processing operations. This service is responsible for managing remote access connections and routing traffic between different networks, making it a high-value target for attackers seeking initial footholds or lateral movement opportunities within an enterprise environment. The core technical issue stems from improper validation of input parameters when handling specific types of network packets destined for the RRAS component. Specifically, the software fails to adequately verify that data indices remain within the allocated memory boundaries before attempting to read them. This lack of rigorous bounds checking allows a malicious actor who can send crafted network traffic to the vulnerable system to trigger an access violation where the application reads from memory locations outside the intended buffer space.
From a technical perspective, this flaw is classified under CWE-125, which denotes Out-of-bounds Read vulnerabilities. The exploitation mechanism relies on the attacker constructing specially formatted packets that cause the RRAS service to interpret invalid indices as valid pointers or offsets within its internal data structures. When these malformed inputs are processed, the system attempts to retrieve information from memory addresses that were not allocated for this specific operation. While out-of-bounds reads typically do not allow direct code execution like buffer overflows, they provide a powerful mechanism for Information Disclosure. By carefully crafting requests and analyzing the responses or side-channel effects such as timing differences or error messages, an attacker can potentially extract sensitive data residing in adjacent memory regions. This could include authentication tokens, cryptographic keys, internal network topology details, or other confidential information stored within the process space of the RRAS service.
The operational impact of this vulnerability is significant due to the privileged nature of the Routing and Remote Access Service. Because RRAS often runs with high-level system privileges, any successful exploitation grants an unauthorized attacker a deeper level of insight into the internal workings of the Windows operating system than would be possible through standard user-space applications. This disclosure can serve as a precursor to more severe attacks. For instance, leaked memory contents might reveal stack addresses or heap layouts that facilitate further exploitation techniques such as return-oriented programming (ROP) chains. Furthermore, in environments where RRAS is used for virtual private network connections, the exposure of session data could lead to unauthorized access to protected resources behind the firewall. The vulnerability affects systems where the role has been installed and configured, meaning any organization relying on Windows-based routing infrastructure is potentially at risk if patches are not applied promptly.
In terms of threat modeling, this vulnerability aligns with ATT&CK technique T1005, which covers Data from Local System, specifically under the sub-technique for data staged or collected via memory scraping techniques enabled by information disclosure flaws. It also relates to reconnaissance activities where attackers gather system configuration details to map out network segments and identify high-value targets within an internal infrastructure. The ability to read arbitrary memory locations effectively breaks the isolation boundaries that operating systems strive to maintain, undermining the confidentiality guarantees provided by modern security architectures.
Mitigation strategies must prioritize immediate patching through official Microsoft update channels, as this is a remote code execution or information disclosure vulnerability in core system components. Administrators should ensure that all Windows servers running the RRAS role are updated with the latest cumulative updates released by Microsoft to address these memory safety issues. In addition to applying patches, organizations should implement network segmentation and firewall rules to restrict access to RRAS services only from trusted IP ranges, thereby reducing the attack surface available to potential adversaries. Monitoring for unusual traffic patterns directed at routing ports can also aid in early detection of exploitation attempts. Regular security audits and vulnerability assessments are essential to ensure that no legacy systems remain unpatched, as these often serve as entry points for sophisticated threat actors leveraging such memory corruption flaws.