Vulnerability Description
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.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Zyxel | Gs1900-8 Firmware | < 2.50\(aahh.0\)c0 |
| Zyxel | Gs1900-8 | - |
| Zyxel | Gs1900-8Hp Firmware | < 2.50\(aahi.0\)c0 |
| Zyxel | Gs1900-8Hp | - |
| Zyxel | Gs1900-10Hp Firmware | < 2.50\(aazi.0\)c0 |
| Zyxel | Gs1900-10Hp | - |
| Zyxel | Gs1900-16 Firmware | < 2.50\(aahj.0\)c0 |
| Zyxel | Gs1900-16 | - |
| Zyxel | Gs1900-24E Firmware | < 2.50\(aahk.0\)c0 |
| Zyxel | Gs1900-24E | - |
| Zyxel | Gs1900-24 Firmware | < 2.50\(aahl.0\)c0 |
| Zyxel | Gs1900-24 | - |
| Zyxel | Gs1900-24Hp Firmware | < 2.50\(aahm.0\)c0 |
| Zyxel | Gs1900-24Hp | - |
| Zyxel | Gs1900-48 Firmware | < 2.50\(aahn.0\)c0 |
| Zyxel | Gs1900-48 | - |
| Zyxel | Gs1900-48Hp Firmware | < 2.50\(aaho.0\)c0 |
| Zyxel | Gs1900-48Hp | - |
Related Weaknesses (CWE)
References
- https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.htmlExploitThird Party Advisory
- https://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtmlVendor Advisory
- https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.htmlExploitThird Party Advisory
- https://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtmlVendor Advisory
FAQ
What is CVE-2019-15802?
CVE-2019-15802 is a vulnerability with a CVSS score of 5.9 (MEDIUM). 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....
How severe is CVE-2019-15802?
CVE-2019-15802 has been rated MEDIUM with a CVSS base score of 5.9/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2019-15802?
Check the references section above for vendor advisories and patch information. Affected products include: Zyxel Gs1900-8 Firmware, Zyxel Gs1900-8, Zyxel Gs1900-8Hp Firmware, Zyxel Gs1900-8Hp, Zyxel Gs1900-10Hp Firmware.