CVE-2019-15802

CVE-2019-15802 is a medium-severity vulnerability in Zyxel Gs1900-8 Firmware with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-798.

Key facts

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.

Frequently asked questions

What is CVE-2019-15802?
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.
How severe is CVE-2019-15802?
CVE-2019-15802 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2019-15802 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-15802?
CVE-2019-15802 primarily affects Zyxel Gs1900-8 Firmware. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-15802?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-15802 published?
CVE-2019-15802 was published on 2019-11-14 and last updated on 2026-06-17.

References

Affected products (9)

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