CVE-2019-15802

Public Exploit

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.

Category

5.9
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.29%
Vendor Advisory zyxel.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.html third party advisory exploit
https://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtml vendor advisory

Frequently Asked Questions

What is the severity of CVE-2019-15802?
CVE-2019-15802 has been scored as a medium severity vulnerability.
How to fix CVE-2019-15802?
To fix CVE-2019-15802, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-15802 being actively exploited in the wild?
It is possible that CVE-2019-15802 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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