The vulnerability stems from the use of a zero‑filled initialization vector in AES‑CBC encryption on the device. Because the same IV is reused for every encryption, identical plaintext blocks produce identical ciphertext blocks, enabling an attacker to perform replay attacks or to correlate ciphertext with known plaintext. This directly threatens the confidentiality of data transmitted by the router.

Acer’s Connect M6E 5G Portable WiFi Router is affected. No specific firmware version information is provided, so all current installations of this model may be vulnerable.

The CVSS score of 6.9 places the issue in the medium severity range. EPSS is not available and the vulnerability is not listed in the CISA KEV catalog. An attacker who can intercept traffic between the router and its clients can exploit the static IV to replay captured frames or to decrypt known plaintext segments, potentially gaining access to sensitive information transmitted over the network.