CVE-2019-15803
CVSS V2 Medium 6.4
CVSS V3 Critical 9.1
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.
Overview
- CVE ID
- CVE-2019-15803
- Assigner
- cve@mitre.org
- Vulnerability Status
- Analyzed
- Published Version
- 2019-11-14T21:15:11
- Last Modified Date
- 2020-08-24T17:37:01
Weakness Enumerations
CPE Configuration (Product)
| CPE | Vulnerable | Operator | Version Start | Version End |
|---|---|---|---|---|
| AND | ||||
| cpe:2.3:o:zyxel:gs1900-8_firmware:*:*:*:*:*:*:*:* | 1 | OR | 2.50\(aahh.0\)c0 | |
| cpe:2.3:h:zyxel:gs1900-8:-:*:*:*:*:*:*:* | 0 | OR | ||
| AND | ||||
| cpe:2.3:o:zyxel:gs1900-8hp_firmware:*:*:*:*:*:*:*:* | 1 | OR | 2.50\(aahi.0\)c0 | |
| cpe:2.3:h:zyxel:gs1900-8hp:-:*:*:*:*:*:*:* | 0 | OR | ||
| AND | ||||
| cpe:2.3:o:zyxel:gs1900-10hp_firmware:*:*:*:*:*:*:*:* | 1 | OR | 2.50\(aazi.0\)c0 | |
| cpe:2.3:h:zyxel:gs1900-10hp:-:*:*:*:*:*:*:* | 0 | OR | ||
| AND | ||||
| cpe:2.3:o:zyxel:gs1900-16_firmware:*:*:*:*:*:*:*:* | 1 | OR | 2.50\(aahj.0\)c0 | |
| cpe:2.3:h:zyxel:gs1900-16:-:*:*:*:*:*:*:* | 0 | OR | ||
| AND | ||||
| cpe:2.3:o:zyxel:gs1900-24e_firmware:*:*:*:*:*:*:*:* | 1 | OR | 2.50\(aahk.0\)c0 | |
| cpe:2.3:h:zyxel:gs1900-24e:-:*:*:*:*:*:*:* | 0 | OR | ||
| AND | ||||
| cpe:2.3:o:zyxel:gs1900-24_firmware:*:*:*:*:*:*:*:* | 1 | OR | 2.50\(aahl.0\)c0 | |
| cpe:2.3:h:zyxel:gs1900-24:-:*:*:*:*:*:*:* | 0 | OR | ||
| AND | ||||
| cpe:2.3:o:zyxel:gs1900-24hp_firmware:*:*:*:*:*:*:*:* | 1 | OR | 2.50\(aahm.0\)c0 | |
| cpe:2.3:h:zyxel:gs1900-24hp:-:*:*:*:*:*:*:* | 0 | OR | ||
| AND | ||||
| cpe:2.3:o:zyxel:gs1900-48_firmware:*:*:*:*:*:*:*:* | 1 | OR | 2.50\(aahn.0\)c0 | |
| cpe:2.3:h:zyxel:gs1900-48:-:*:*:*:*:*:*:* | 0 | OR | ||
| AND | ||||
| cpe:2.3:o:zyxel:gs1900-48hp_firmware:*:*:*:*:*:*:*:* | 1 | OR | 2.50\(aaho.0\)c0 | |
| cpe:2.3:h:zyxel:gs1900-48hp:-:*:*:*:*:*:*:* | 0 | OR |
CVSS Version 2
- Version
- 2.0
- Vector String
- AV:N/AC:L/Au:N/C:P/I:P/A:N
- Access Vector
- NETWORK
- Access Compatibility
- LOW
- Authentication
- NONE
- Confidentiality Impact
- PARTIAL
- Integrity Impact
- PARTIAL
- Availability Impact
- NONE
- Base Score
- 6.4
- Severity
- MEDIUM
- Exploitability Score
- 10
- Impact Score
- 4.9
CVSS Version 3
- Version
- 3.1
- Vector String
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- Attack Vector
- NETWORK
- Attack Compatibility
- LOW
- Privileges Required
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality Impact
- HIGH
- Availability Impact
- NONE
- Base Score
- 9.1
- Base Severity
- CRITICAL
- Exploitability Score
- 3.9
- Impact Score
- 5.2
References
| Reference URL | Reference Tags |
|---|---|
| https://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtml | Vendor Advisory |
| https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.html | Exploit Third Party Advisory |
Sources
| Source Name | Source URL |
|---|---|
| NIST | https://nvd.nist.gov/vuln/detail/CVE-2019-15803 |
| MITRE | https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-15803 |
History
| Created | Old Value | New Value | Data Type | Notes |
|---|---|---|---|---|
| 2022-05-10 16:35:53 | Added to TrackCVE | |||
| 2022-12-04 06:24:41 | 2019-11-14T21:15Z | 2019-11-14T21:15:11 | CVE Published Date | updated |
| 2022-12-04 06:24:41 | 2020-08-24T17:37:01 | CVE Modified Date | updated | |
| 2022-12-04 06:24:41 | Analyzed | Vulnerability Status | updated |