CVE-2025-8979 is a high-severity vulnerability affecting the Tenda AC15 router, specifically version 15.13.07.13. The flaw resides in the Firmware Update Handler component, within functions such as check_fw_type, split_fireware, and check_fw. These functions are responsible for verifying the authenticity of firmware update data. Due to insufficient verification mechanisms, an attacker can manipulate the firmware update process remotely, potentially injecting malicious firmware or unauthorized code. The vulnerability does not require user interaction but does require high privileges (PR:H) on the device, indicating that the attacker must have some level of authenticated access or control. The attack complexity is high, meaning exploitation requires advanced skills or conditions, and no known exploits are currently observed in the wild. The CVSS 4.0 score of 7.5 reflects a high impact on confidentiality, integrity, and availability, with the vulnerability allowing remote code execution or firmware tampering if successfully exploited. The lack of secure verification in the firmware update process could lead to persistent compromise of the device, enabling attackers to intercept network traffic, launch further attacks on connected systems, or disrupt network availability. Given the critical role of routers in network infrastructure, this vulnerability poses a significant risk to environments relying on the affected Tenda AC15 firmware version.

For European organizations, the exploitation of CVE-2025-8979 could have severe consequences. Compromised routers can serve as entry points for attackers to infiltrate internal networks, leading to data breaches, espionage, or disruption of business operations. Confidential information transmitted through the network could be intercepted or altered, undermining data integrity and privacy compliance obligations such as GDPR. The persistence of malicious firmware could evade detection by standard security tools, prolonging exposure. Additionally, disruption of network availability could impact critical services, especially in sectors like finance, healthcare, and government. The high complexity of exploitation somewhat limits widespread attacks but does not eliminate risk, particularly from well-resourced threat actors targeting strategic organizations. The absence of known exploits in the wild currently reduces immediate threat but public disclosure increases the risk of future exploitation attempts.

1. Immediate firmware update: Organizations should verify if Tenda has released a patched firmware version addressing CVE-2025-8979 and apply it promptly. 2. Network segmentation: Isolate vulnerable Tenda AC15 devices from critical network segments to limit potential lateral movement if compromised. 3. Access control: Restrict administrative access to the router's management interface using strong authentication methods and limit access to trusted personnel and IP addresses. 4. Monitor firmware update processes: Implement logging and alerting for firmware update attempts to detect unauthorized or suspicious activities. 5. Device replacement: For high-security environments, consider replacing affected Tenda AC15 devices with models from vendors with stronger security track records or verified secure update mechanisms. 6. Incident response readiness: Prepare for potential compromise scenarios by maintaining backups, network monitoring, and incident response plans tailored to router-level threats. 7. Vendor engagement: Engage with Tenda support channels to obtain official guidance and updates regarding this vulnerability.