{"id":"CVE-2019-15803","state":"PUBLISHED","title":"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 diag","description":"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.","publishedAt":"2019-11-14T20:15:56.000Z","updatedAt":"2024-08-05T00:56:22.468Z","severity":null,"assigner":"mitre","products":["n/a n/a"],"affected":[{"vendor":"n/a","product":"n/a","versions":[{"version":"n/a","status":"affected"}]}],"references":["https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.html","https://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtml"],"weaknesses":[],"ingestedAt":"2026-10-29T19:45:33.607Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2019/15xxx/CVE-2019-15803.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2019-15803","state":"PUBLISHED","datePublished":"2019-11-14T20:15:56.000Z","dateUpdated":"2024-08-05T00:56:22.468Z","assignerShortName":"mitre","assignerOrgId":"8254265b-2729-46b6-b9e3-3dfca2d5bfca","dateReserved":"2019-08-29T00:00:00.000Z"},"containers":{"cna":{"descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"n/a","product":"n/a","versions":[{"version":"n/a","status":"affected"}]}],"references":[{"url":"https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.html","tags":["x_refsource_MISC"]},{"url":"https://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtml","tags":["x_refsource_CONFIRM"]}],"problemTypes":[{"descriptions":[{"description":"n/a","lang":"en","type":"text"}]}],"providerMetadata":{"shortName":"mitre","dateUpdated":"2019-11-14T20:15:56.000Z","orgId":"8254265b-2729-46b6-b9e3-3dfca2d5bfca"},"x_legacyV4Record":{"CVE_data_meta":{"ASSIGNER":"cve@mitre.org","ID":"CVE-2019-15803","STATE":"PUBLIC"},"affects":{"vendor":{"vendor_data":[{"product":{"product_data":[{"product_name":"n/a","version":{"version_data":[{"version_value":"n/a"}]}}]},"vendor_name":"n/a"}]}},"data_format":"MITRE","data_type":"CVE","data_version":"4.0","description":{"description_data":[{"lang":"eng","value":"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."}]},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"n/a"}]}]},"references":{"reference_data":[{"name":"https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.html","refsource":"MISC","url":"https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.html"},{"name":"https://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtml","refsource":"CONFIRM","url":"https://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtml"}]}}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.html","tags":["x_refsource_MISC","x_transferred"]},{"url":"https://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtml","tags":["x_refsource_CONFIRM","x_transferred"]}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2024-08-05T00:56:22.468Z"}}]}}}