A null byte interaction error has been discovered in the code that the telnetd_startup daemon uses to construct a pair of ephemeral passwords that allow a user to spawn a telnet service on the router, and to ensure that the telnet service persists upon reboot. By means of a crafted exchange of UDP packets, an unauthenticated attacker on the local network can leverage this null byte interaction error in such a way as to make those ephemeral passwords predictable (with 1-in-94 odds). Since the attacker must manipulate data processed by the OpenSSL function RSA_public_decrypt(), successful exploitation of this vulnerability depends on the use of an unpadded RSA cipher (CVE-2022-25218).
CPE | Name | Operator | Version |
---|---|---|---|
k2_firmware | le | 22.5.9.163 | |
k2g_firmware | le | 22.6.3.20 | |
k2p_firmware | le | 20.4.1.7 | |
k3_firmware | le | 21.5.37.246 | |
k3c_firmware | le | 32.1.15.93 |