WAVLINK WN535M1 and WN535M3 routers running firmware prior to M35M1V250922 contain an unauthenticated arbitrary file write vulnerability that allows remote attackers to overwrite any file on the device by sending a crafted payload to the syncserver daemon on TCP port 13136. The daemon, which runs as root and requires no authentication, accepts a 100-byte filename field in its protocol header without path canonicalization, allowing attackers to supply an absolute path and write arbitrary content to overwrite startup scripts or credential stores to achieve persistent system compromise.

WAVLINK WN535M1 and WN535M3 routers running firmware prior to M35M1V250922 contain an unauthenticated OS command injection vulnerability that allows remote attackers to execute arbitrary commands as root by sending crafted filenames to the syncserver daemon on TCP port 13136. The daemon interpolates attacker-controlled filename input containing shell metacharacters into a shell command string via sprintf() and passes it to system() without sanitization, enabling root-level command execution on the device.

A vulnerability was determined in Wavlink WN531P3 and WN535M1 V250922. Affected by this vulnerability is the function strcpy of the file /etc/lighttpd/www/cgi-bin/exportpingortrace.cgi of the component Export Pingortrace CGI. Executing a manipulation of the argument HTTPCOOKIE can lead to stack-based buffer overflow. The attack may be launched remotely. The exploit has been publicly disclosed and may be utilized. The vendor was contacted early about this disclosure.