An issue was discovered on Zyxel GS1900 devices with firmware before 2.50(AAHH.0)C0.
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-798.
Summary
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.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 18
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:zyxel:gs1900-8_firmware:*:*:*:*:*:*:*:* | before 2.50\(aahh.0\)c0 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:gs1900-8:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:gs1900-8hp_firmware:*:*:*:*:*:*:*:* | before 2.50\(aahi.0\)c0 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:gs1900-8hp:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:gs1900-10hp_firmware:*:*:*:*:*:*:*:* | before 2.50\(aazi.0\)c0 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:gs1900-10hp:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:gs1900-16_firmware:*:*:*:*:*:*:*:* | before 2.50\(aahj.0\)c0 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:gs1900-16:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:gs1900-24e_firmware:*:*:*:*:*:*:*:* | before 2.50\(aahk.0\)c0 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:gs1900-24e:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
- cpe:2.3:o:zyxel:gs1900-8_firmware:*:*:*:*:*:*:*:* Versions before 2.50\(aahh.0\)c0 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:gs1900-8:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:gs1900-8hp_firmware:*:*:*:*:*:*:*:* Versions before 2.50\(aahi.0\)c0 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:gs1900-8hp:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:gs1900-10hp_firmware:*:*:*:*:*:*:*:* Versions before 2.50\(aazi.0\)c0 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:gs1900-10hp:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:gs1900-16_firmware:*:*:*:*:*:*:*:* Versions before 2.50\(aahj.0\)c0 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:gs1900-16:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:gs1900-24e_firmware:*:*:*:*:*:*:*:* Versions before 2.50\(aahk.0\)c0 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:gs1900-24e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
Show 8 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:zyxel:gs1900-24_firmware:*:*:*:*:*:*:*:* | before 2.50\(aahl.0\)c0 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:gs1900-24:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:gs1900-24hp_firmware:*:*:*:*:*:*:*:* | before 2.50\(aahm.0\)c0 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:gs1900-24hp:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:gs1900-48_firmware:*:*:*:*:*:*:*:* | before 2.50\(aahn.0\)c0 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:gs1900-48:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:gs1900-48hp_firmware:*:*:*:*:*:*:*:* | before 2.50\(aaho.0\)c0 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:gs1900-48hp:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
- cpe:2.3:o:zyxel:gs1900-24_firmware:*:*:*:*:*:*:*:* Versions before 2.50\(aahl.0\)c0 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:gs1900-24:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:gs1900-24hp_firmware:*:*:*:*:*:*:*:* Versions before 2.50\(aahm.0\)c0 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:gs1900-24hp:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:gs1900-48_firmware:*:*:*:*:*:*:*:* Versions before 2.50\(aahn.0\)c0 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:gs1900-48:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:gs1900-48hp_firmware:*:*:*:*:*:*:*:* Versions before 2.50\(aaho.0\)c0 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:gs1900-48hp:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2019-15802
- 2026-10-03 Alias added: GHSA-fmpq-8rp4-f234
References
More Zyxel Gs1900-10hp Firmware vulnerabilities
- TI-2026-06387 Stack-based buffer overflow in Zyxel GS1900-48HPv2 firmware KEVCVSS 3.1HIGH 8.8
- TI-2019-11869 An issue was discovered on Zyxel GS1900 devices with firmware before 2.50(AAHH.0)C0. CVSS 3.1CRITICAL 9.8
- TI-2016-01221 Cisco NX-OS 6.0(2)U6(1) through 6.0(2)U6(5) on Nexus 3000 devices and 6.0(2)A6(1) through… CVSS 3.0CRITICAL 9.8
- TI-2015-05062 Belkin F9K1102 2 devices with firmware 2.10.17 rely on client-side JavaScript code for… CVSS 3.0CRITICAL 9.8
- TI-2015-05061 The web management interface on Belkin F9K1102 2 devices with firmware 2.10.17 has a… CVSS 3.0CRITICAL 9.8
- TI-2019-11872 An issue was discovered on Zyxel GS1900 devices with firmware before 2.50(AAHH.0)C0. CVSS 3.1CRITICAL 9.1
Sources
- CVE-2019-15802 · CVE Program
- CVE-2019-15802 · NVD
- FIRST EPSS
- GHSA-fmpq-8rp4-f234 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences