CVE-2025-12232 is a remote buffer overflow vulnerability identified in the Tenda CH22 router firmware version 1.0.0.1. The flaw resides in the fromSafeClientFilter function within the /goform/SafeClientFilter endpoint, where improper handling of the 'page' argument allows an attacker to overflow a buffer. This vulnerability can be exploited remotely without requiring authentication or user interaction, making it highly accessible to attackers. The buffer overflow can lead to arbitrary code execution, allowing attackers to take full control of the device, manipulate network traffic, or disrupt services. The CVSS 4.0 score of 8.7 reflects the high impact on confidentiality, integrity, and availability, combined with low attack complexity and no required privileges. Although no active exploitation has been reported, the availability of a public exploit increases the likelihood of future attacks. The vulnerability affects a specific firmware version, so organizations using Tenda CH22 routers with this firmware are directly impacted. The lack of official patches at the time of disclosure necessitates immediate mitigation steps to reduce exposure. Given the role of routers in network infrastructure, successful exploitation could facilitate lateral movement, data interception, or denial of service within affected networks.

For European organizations, exploitation of CVE-2025-12232 could result in complete compromise of affected Tenda CH22 routers, leading to unauthorized access to internal networks, interception or manipulation of sensitive data, and disruption of network availability. This is particularly critical for enterprises and service providers relying on these devices for perimeter security or network segmentation. The vulnerability's remote exploitability without authentication increases the risk of widespread attacks, potentially impacting critical infrastructure, government networks, and private sector entities. Compromised routers could serve as entry points for further attacks, including ransomware or espionage campaigns. The impact extends to loss of confidentiality, integrity, and availability of network communications, which could have regulatory and reputational consequences under European data protection laws such as GDPR. Organizations with limited patch management capabilities or those unaware of the vulnerability are especially vulnerable. The presence of a public exploit further elevates the threat landscape, necessitating urgent attention to mitigate risks.

1. Immediately identify and inventory all Tenda CH22 routers running firmware version 1.0.0.1 within the network. 2. If an official patch becomes available from Tenda, apply it promptly to remediate the vulnerability. 3. In the absence of a patch, disable remote management interfaces and restrict access to the /goform/SafeClientFilter endpoint using firewall rules or access control lists. 4. Segment vulnerable devices on isolated network segments to limit exposure and prevent lateral movement. 5. Monitor network traffic for unusual requests targeting the /goform/SafeClientFilter endpoint or anomalous patterns indicative of exploitation attempts. 6. Employ intrusion detection/prevention systems (IDS/IPS) with updated signatures to detect attempts to exploit this vulnerability. 7. Educate network administrators about the vulnerability and ensure they follow secure configuration best practices for Tenda devices. 8. Consider replacing affected devices with models from vendors with a stronger security track record if patching is not feasible. 9. Regularly review and update network device firmware to minimize exposure to known vulnerabilities.