CVE-2025-15545 is a vulnerability identified in the TP-Link Archer RE605X, a consumer and small business Wi-Fi range extender. The flaw stems from improper input validation (CWE-20) in the device's backup restore functionality. Specifically, the device fails to properly validate unexpected or unrecognized tags within the backup configuration file. When a crafted backup file containing malicious tags is restored, these tags are interpreted by the device's underlying shell environment, enabling execution of arbitrary commands with root-level privileges. This means an attacker who can supply such a malicious backup file can gain full control over the device, allowing them to manipulate configurations, intercept or redirect network traffic, deploy malware, or disrupt device operation. The CVSS 4.0 vector indicates the attack requires adjacent network access (AV:A), high attack complexity (AC:H), no privileges required (PR:H means high privileges are required, so this is a correction: PR:H means privileges are required), no user interaction (UI:N), and results in high confidentiality, integrity, and availability impacts. The vulnerability is currently not known to be exploited in the wild, and no patches have been published yet. The device is typically managed via a web interface or local network, so exploitation would require access to the device's management network or physical access. The root cause is the lack of strict validation of backup file contents before processing, allowing shell injection via crafted tags.

For European organizations, this vulnerability poses a significant risk especially to small and medium enterprises or home offices relying on the Archer RE605X for network extension. Successful exploitation grants attackers root-level control over the device, enabling them to compromise network confidentiality by intercepting or redirecting traffic, integrity by altering device configurations or firmware, and availability by disabling the device or network services. This can lead to broader network compromise, data breaches, or denial of service. Given the device's role in extending Wi-Fi coverage, attackers could use it as a foothold to pivot into internal networks. The requirement for high privileges and adjacent network access somewhat limits remote exploitation but insider threats or compromised internal hosts could leverage this vulnerability. The absence of known exploits currently provides a window for mitigation before active attacks emerge.

European organizations should immediately audit their network to identify deployments of the TP-Link Archer RE605X. Until a patch is available, restrict access to the device's management interfaces by implementing network segmentation and access control lists limiting management access to trusted administrators only. Disable remote backup restore functionality if possible or restrict backup file restoration to verified files only. Monitor network traffic for unusual backup file uploads or configuration changes. Employ network intrusion detection systems to flag suspicious activity targeting these devices. Maintain an inventory of affected devices and subscribe to TP-Link security advisories for timely patch releases. Consider replacing vulnerable devices in critical environments with alternatives that have robust security track records. Additionally, enforce strong authentication and regularly update device firmware to reduce the risk of privilege escalation.