CVE-2022-45521 is a high-severity vulnerability identified in the Tenda W30E router firmware version 1.0.1.25(633). The vulnerability is a stack-based buffer overflow triggered via the 'page' parameter in the /goform/SafeUrlFilter endpoint. A stack overflow occurs when more data is written to a buffer located on the stack than it can hold, potentially overwriting adjacent memory and leading to unpredictable behavior. In this case, the overflow can be exploited remotely over the network without requiring any authentication or user interaction, as indicated by the CVSS vector (AV:N/AC:L/PR:N/UI:N). The vulnerability impacts availability (A:H) but does not affect confidentiality or integrity directly. Exploiting this flaw could cause the device to crash or reboot, resulting in denial of service (DoS) conditions. Although no known exploits have been reported in the wild, the ease of exploitation and lack of required privileges make this a significant risk. The affected product is a consumer-grade router model, which is commonly deployed in home and small office environments. The vulnerability is classified under CWE-787 (Out-of-bounds Write), which is a common category for memory corruption issues that can lead to crashes or potentially arbitrary code execution if further exploited. However, no evidence currently suggests code execution is achievable through this specific flaw. No patches or vendor advisories have been linked, indicating that mitigation may require manual intervention or firmware updates once available.

For European organizations, the primary impact of CVE-2022-45521 is the potential for disruption of network connectivity due to denial of service on affected Tenda W30E routers. This can interrupt internet access, internal communications, and critical business operations reliant on stable network infrastructure. While the vulnerability does not directly compromise data confidentiality or integrity, the loss of availability can affect operational continuity, especially for small businesses or remote offices using these routers as their primary gateway. Additionally, compromised routers could be leveraged as part of larger botnets or attack campaigns if attackers develop further exploits. The lack of authentication and user interaction requirements increases the risk of automated scanning and exploitation attempts. European organizations with distributed or remote workforces using consumer-grade networking equipment are particularly vulnerable. The absence of patches or vendor guidance complicates mitigation efforts, potentially prolonging exposure. Critical infrastructure sectors relying on stable network access may experience cascading effects if network disruptions occur.

1. Immediate mitigation should include isolating affected Tenda W30E routers from critical network segments to limit exposure. 2. Network administrators should implement strict ingress filtering and firewall rules to restrict access to router management interfaces, especially blocking external access to the /goform/SafeUrlFilter endpoint. 3. Monitor network traffic for unusual requests targeting the vulnerable parameter to detect potential exploitation attempts. 4. Where possible, replace Tenda W30E routers with alternative models from vendors with active security support and patch availability. 5. If replacement is not feasible, consider deploying network-level protections such as intrusion prevention systems (IPS) that can detect and block exploitation patterns. 6. Regularly check for firmware updates from Tenda and apply them promptly once a patch addressing this vulnerability is released. 7. Educate users and IT staff about the risks of using outdated consumer-grade network devices in organizational environments and encourage adoption of enterprise-grade equipment with robust security features.