An issue was discovered on Zyxel GS1900 devices with firmware before 2.50(AAHH.0)C0. The firmware hashes and encrypts passwords using a hardcoded cryptographic key in sal_util_str_encrypt() in libsal.so.0.0. The parameters (salt, IV, and key data) are used to encrypt and decrypt all passwords using AES256 in CBC mode. With the parameters known, all previously encrypted passwords can be decrypted. This includes the passwords that are part of configuration backups or otherwise embedded as part of the firmware.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 5.9, indicating it can be exploited remotely over the network but requires specific conditions to be met without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts confidentiality (data exposure), for affected systems. Impacting 18 products from zyxel, from zyxel, from zyxel and 15 others, organizations running these solutions should prioritize assessment and patching.
First disclosed in 2019, this vulnerability was reported during a period defined by widespread IoT adoption challenges, mobile security concerns, and the emergence of advanced persistent threat (APT) techniques. Contemporary mitigation strategies focused on secure development practices and third-party component vetting.
2019-11-14T21:15:11.797
2024-11-21T04:29:29.790
Modified
CVSSv3.1: 5.9 (MEDIUM)
AV:N/AC:M/Au:N/C:P/I:N/A:N
8.6
2.9
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Operating System | zyxel | gs1900-8_firmware | < 2.50\(aahh.0\)c0 | Yes |
| Hardware | zyxel | gs1900-8 | - | No |
| Operating System | zyxel | gs1900-8hp_firmware | < 2.50\(aahi.0\)c0 | Yes |
| Hardware | zyxel | gs1900-8hp | - | No |
| Operating System | zyxel | gs1900-10hp_firmware | < 2.50\(aazi.0\)c0 | Yes |
| Hardware | zyxel | gs1900-10hp | - | No |
| Operating System | zyxel | gs1900-16_firmware | < 2.50\(aahj.0\)c0 | Yes |
| Hardware | zyxel | gs1900-16 | - | No |
| Operating System | zyxel | gs1900-24e_firmware | < 2.50\(aahk.0\)c0 | Yes |
| Hardware | zyxel | gs1900-24e | - | No |
| Operating System | zyxel | gs1900-24_firmware | < 2.50\(aahl.0\)c0 | Yes |
| Hardware | zyxel | gs1900-24 | - | No |
| Operating System | zyxel | gs1900-24hp_firmware | < 2.50\(aahm.0\)c0 | Yes |
| Hardware | zyxel | gs1900-24hp | - | No |
| Operating System | zyxel | gs1900-48_firmware | < 2.50\(aahn.0\)c0 | Yes |
| Hardware | zyxel | gs1900-48 | - | No |
| Operating System | zyxel | gs1900-48hp_firmware | < 2.50\(aaho.0\)c0 | Yes |
| Hardware | zyxel | gs1900-48hp | - | No |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For zyxel's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.