CVE-2025-8299 is a high-severity heap-based buffer overflow vulnerability identified in the Realtek rtl81xx SDK Wi-Fi driver, specifically within the MgntActSet_TEREDO_SET_RS_PACKET function. This flaw arises due to improper validation of the length of user-supplied data before copying it into a fixed-length heap buffer. Because of this, an attacker who already has the ability to execute code with low privileges on the affected system can exploit this vulnerability to overflow the heap buffer, leading to local privilege escalation. Successful exploitation allows the attacker to execute arbitrary code with SYSTEM-level privileges, effectively gaining full control over the compromised system. The vulnerability is classified under CWE-122 (Heap-based Buffer Overflow) and has a CVSS v3.0 score of 8.8, indicating high severity. The attack vector is local (AV:L), requiring low attack complexity (AC:L) and low privileges (PR:L), but no user interaction (UI:N). The scope is changed (S:C), meaning the vulnerability affects resources beyond the initially compromised component, and it impacts confidentiality, integrity, and availability at a high level (C:H/I:H/A:H). No public exploits are currently known in the wild, and no patches have been linked yet. The affected product version is 1030.38.712.2019 of the Realtek rtl81xx SDK, which is commonly integrated into Wi-Fi drivers for network interface cards and embedded devices. This vulnerability is particularly dangerous because it enables attackers to elevate privileges from a low-privileged user context to SYSTEM, potentially leading to full system compromise, installation of persistent malware, or lateral movement within a network.

For European organizations, this vulnerability poses a significant risk, especially in environments where Realtek rtl81xx SDK-based Wi-Fi drivers are deployed on endpoints, servers, or embedded systems. The ability for an attacker to escalate privileges locally means that any initial foothold gained through phishing, malware, or insider threats could be amplified to full system control. This can lead to data breaches involving sensitive personal data protected under GDPR, disruption of critical business operations, and potential compromise of network infrastructure. Industries with high reliance on wireless connectivity, such as manufacturing, healthcare, finance, and government, are particularly vulnerable. The impact extends to operational technology environments where embedded devices using these drivers are present, potentially affecting industrial control systems. Additionally, the high severity and SYSTEM-level code execution capability increase the risk of ransomware deployment or espionage activities. Given the lack of known public exploits, the threat is currently theoretical but could become active once exploit code is developed and disseminated.

European organizations should take immediate steps to mitigate this vulnerability. First, they should inventory all devices and systems using Realtek rtl81xx SDK Wi-Fi drivers, focusing on the affected version 1030.38.712.2019. Since no official patches are currently available, organizations should monitor Realtek’s security advisories and apply updates promptly once released. In the interim, applying strict local privilege separation and minimizing the number of users with local code execution capabilities can reduce risk. Employing endpoint detection and response (EDR) solutions to monitor for anomalous behavior related to privilege escalation attempts is recommended. Network segmentation should be enforced to limit lateral movement from compromised endpoints. Additionally, disabling or restricting the use of Teredo tunneling if not required may reduce the attack surface related to the vulnerable function. Organizations should also conduct regular vulnerability assessments and penetration tests focusing on local privilege escalation vectors. Finally, educating users about the risks of executing untrusted code locally can help prevent initial compromise.