CVE-2019-15803
https://notcve.org/view.php?id=CVE-2019-15803
An issue was discovered on Zyxel GS1900 devices with firmware before 2.50(AAHH.0)C0. Through an undocumented sequence of keypresses, undocumented functionality is triggered. A diagnostics shell is triggered via CTRL-ALT-t, which prompts for the password returned by fds_sys_passDebugPasswd_ret(). The firmware contains access control checks that determine if remote users are allowed to access this functionality. The function that performs this check (fds_sys_remoteDebugEnable_ret in libfds.so) always return TRUE with no actual checks performed. • https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.html https://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtml • CWE-287: Improper Authentication •
CVE-2019-15804
https://notcve.org/view.php?id=CVE-2019-15804
An issue was discovered on Zyxel GS1900 devices with firmware before 2.50(AAHH.0)C0. By sending a signal to the CLI process, undocumented functionality is triggered. Specifically, a menu can be triggered by sending the SIGQUIT signal to the CLI application (e.g., through CTRL+\ via SSH). The access control check for this menu does work and prohibits accessing the menu, which contains "Password recovery for specific user" options. The menu is believed to be accessible using a serial console. • https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.html https://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtml •
CVE-2015-7256
https://notcve.org/view.php?id=CVE-2015-7256
ZyXEL NWA1100-N, NWA1100-NH, NWA1121-NI, NWA1123-AC, and NWA1123-NI access points; P-660HN-51, P-663HN-51, VMG1312-B10A, VMG1312-B30A, VMG1312-B30B, VMG4380-B10A, VMG8324-B10A, VMG8924-B10A, VMG8924-B30A, and VSG1435-B101 DSL CPEs; PMG5318-B20A GPONs; SBG3300-N000, SBG3300-NB00, and SBG3500-N000 small business gateways; GS1900-8 and GS1900-24 switches; and C1000Z, Q1000, FR1000Z, and P8702N project models use non-unique X.509 certificates and SSH host keys. Los puntos de acceso ZyXEL NWA1100-N, NWA1100-NH, NWA1121-NI, NWA1123-AC, NWA1123-NI; los CPE DSL P-660HN-51, P-663HN-51, VMG1312-B10A, VMG1312-B30A, VMG1312-B30B, VMG4380-B10A, VMG8324-B10A, VMG8924-B10A, VMG8924-B30A, VSG1435-B101; las puertas de enlace para pequeñas empresas PMG5318-B20A GPON, SBG3300-N000, SBG3300-NB00, SBG3500-N000; los switches GS1900-8 y GS1900-24 y los modelos de módem C1000Z, Q1000, FR1000Z, P8702N emplean certificados X.509 y claves host de SSH que no son únicos. • http://www.kb.cert.org/vuls/id/566724 http://www.zyxel.com/support/announcement_SSH_private_key_and_certificate_vulnerability.shtml • CWE-310: Cryptographic Issues •