CVE-2026-67596 describes a vulnerability in the CSL 1010 M2M 3G WiFi Module firmware (up to version 2.2.1.4) where the configuration backup file is protected by a weak encryption scheme. Specifically, a single-byte XOR cipher with a static key is used, which can be trivially reversed by unauthenticated attackers. Exploiting this weakness allows attackers to decrypt the Router.cfg backup file and extract all stored secrets in plaintext, including administrative passwords, wireless keys, network credentials, and SIM identifiers. This exposure compromises device security and confidentiality of sensitive credentials. No vendor advisory or patch information is currently available.

An attacker with access to the configuration backup file can recover all stored secrets in plaintext, including web administration and telnet passwords, WPA/WPA2 pre-shared keys, PPPoE and 3G/APN credentials, and SIM identifiers such as IMSI and IMEI. This can lead to unauthorized access to device management interfaces and network services, potentially compromising the device and connected networks. The vulnerability requires local access to the backup file but does not require authentication.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict access to configuration backup files and avoid storing or transmitting them insecurely. Monitor for vendor updates regarding patches or official mitigations.