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. The diagnostics menu allows for reading/writing arbitrary registers and various other configuration parameters which are believed to be related to the network interface chips.
Metrics
Affected Vendors & Products
References
History
No history.
MITRE
Status: PUBLISHED
Assigner: mitre
Published: 2019-11-14T20:15:56
Updated: 2024-08-05T00:56:22.468Z
Reserved: 2019-08-29T00:00:00
Link: CVE-2019-15803
Vulnrichment
No data.
NVD
Status : Analyzed
Published: 2019-11-14T21:15:11.890
Modified: 2020-08-24T17:37:01.140
Link: CVE-2019-15803
Redhat
No data.