CVE-2025-55498 is a buffer overflow vulnerability identified in the Tenda AC6 router firmware version V15.03.06.23_multi. The flaw exists in the fromSetSysTime function, specifically triggered via the 'time' parameter. Buffer overflow vulnerabilities occur when a program writes more data to a buffer than it can hold, potentially overwriting adjacent memory. This can lead to unpredictable behavior including crashes, data corruption, or arbitrary code execution. In this case, exploiting the vulnerability could allow an attacker to execute arbitrary code on the router with the privileges of the affected process, potentially leading to full device compromise. The vulnerability is notable because routers are critical network infrastructure devices that manage traffic and security for connected devices. No CVSS score has been assigned yet, and no known exploits are reported in the wild. The affected version is specific to Tenda AC6 routers running the stated firmware, but no other versions or models are mentioned. The vulnerability was published on August 20, 2025, with the reservation date of August 13, 2025. The lack of patch links suggests that no official fix has been released at the time of this report. Given the nature of buffer overflow vulnerabilities, exploitation typically requires sending specially crafted input to the vulnerable function, which may be accessible remotely or locally depending on the router's interface exposure. The fromSetSysTime function likely relates to setting system time parameters, which may be accessible via the router's web interface or API, potentially increasing the attack surface if exposed externally or insufficiently protected.

For European organizations, this vulnerability poses a significant risk to network security and operational continuity. Compromise of a Tenda AC6 router could allow attackers to intercept, modify, or redirect network traffic, undermining confidentiality and integrity of communications. Attackers could also use the compromised router as a foothold to launch further attacks within the internal network, including lateral movement to critical systems. The availability of the network could be disrupted if the router is crashed or rebooted repeatedly by exploiting the overflow. Given that routers are often deployed at the perimeter of organizational networks, this vulnerability could facilitate man-in-the-middle attacks, data exfiltration, or insertion of malicious payloads into network traffic. The absence of a patch increases the window of exposure, especially if the device is accessible from untrusted networks. Additionally, many small and medium enterprises (SMEs) and home offices in Europe use consumer-grade routers like the Tenda AC6, potentially broadening the impact beyond large enterprises. The lack of known exploits in the wild currently reduces immediate risk, but the vulnerability's presence in widely deployed network infrastructure warrants urgent attention to prevent future exploitation.

Organizations should first identify any Tenda AC6 routers running firmware version V15.03.06.23_multi within their networks. Until an official patch is released, the following specific mitigations are recommended: 1) Restrict access to the router's management interfaces (web UI, APIs) to trusted internal networks only, using firewall rules or VLAN segmentation. 2) Disable remote management features if enabled, especially those accessible from the internet. 3) Monitor network traffic for unusual patterns that could indicate exploitation attempts targeting the time parameter or related functions. 4) Implement network segmentation to isolate critical assets from devices using vulnerable routers. 5) Regularly check for firmware updates from Tenda and apply patches promptly once available. 6) Consider replacing vulnerable devices with models from vendors with stronger security track records if patching is delayed. 7) Employ intrusion detection/prevention systems (IDS/IPS) with signatures or anomaly detection capabilities that could identify exploitation attempts. 8) Educate IT staff about the vulnerability and encourage vigilance for signs of compromise related to router behavior or network anomalies.