On certain TOTOLINK Realtek SDK based routers, an authenticated attacker may execute arbitrary OS commands via the sysCmd parameter to the boafrm/formSysCmd URI, even if the GUI (syscmd.htm) is not available. This allows for full control over the device's internals. This affects A3002RU through 2.0.0, A702R through 2.1.3, N301RT through 2.1.6, N302R through 3.4.0, N300RT through 3.4.0, N200RE through 4.0.0, N150RT through 3.4.0, N100RE through 3.4.0, and N302RE 2.0.2.

A certain router administration interface (that includes Realtek APMIB 0.11f for Boa 0.94.14rc21) stores cleartext administrative passwords in flash memory and in a file. This affects TOTOLINK A3002RU through 2.0.0, A702R through 2.1.3, N301RT through 2.1.6, N302R through 3.4.0, N300RT through 3.4.0, N200RE through 4.0.0, N150RT through 3.4.0, and N100RE through 3.4.0; Rutek RTK 11N AP through 2019-12-12; Sapido GR297n through 2019-12-12; CIK TELECOM MESH ROUTER through 2019-12-12; KCTVJEJU Wireless AP through 2019-12-12; Fibergate FGN-R2 through 2019-12-12; Hi-Wifi MAX-C300N through 2019-12-12; HCN MAX-C300N through 2019-12-12; T-broad GN-866ac through 2019-12-12; Coship EMTA AP through 2019-12-12; and IO-Data WN-AC1167R through 2019-12-12.

A certain router administration interface (that includes Realtek APMIB 0.11f for Boa 0.94.14rc21) allows remote attackers to retrieve the configuration, including sensitive data (usernames and passwords). This affects TOTOLINK A3002RU through 2.0.0, A702R through 2.1.3, N301RT through 2.1.6, N302R through 3.4.0, N300RT through 3.4.0, N200RE through 4.0.0, N150RT through 3.4.0, and N100RE through 3.4.0; Rutek RTK 11N AP through 2019-12-12; Sapido GR297n through 2019-12-12; CIK TELECOM MESH ROUTER through 2019-12-12; KCTVJEJU Wireless AP through 2019-12-12; Fibergate FGN-R2 through 2019-12-12; Hi-Wifi MAX-C300N through 2019-12-12; HCN MAX-C300N through 2019-12-12; T-broad GN-866ac through 2019-12-12; Coship EMTA AP through 2019-12-12; and IO-Data WN-AC1167R through 2019-12-12.

On certain TOTOLINK Realtek SDK based routers, the CAPTCHA text can be retrieved via an {"topicurl":"setting/getSanvas"} POST to the boafrm/formLogin URI, leading to a CAPTCHA bypass. (Also, the CAPTCHA text is not needed once the attacker has determined valid credentials. The attacker can perform router actions via HTTP requests with Basic Authentication.) This affects A3002RU through 2.0.0, A702R through 2.1.3, N301RT through 2.1.6, N302R through 3.4.0, N300RT through 3.4.0, N200RE through 4.0.0, N150RT through 3.4.0, and N100RE through 3.4.0.