Zyxel security advisory for insufficient entropy vulnerability for web authentication tokens generation in GS1900 series switches
CVE: CVE-2024-38270
Summary
Zyxel has released patches for GS1900 series switches affected by an insufficient entropy vulnerability. Users are advised to install them for optimal protection.
What is the vulnerability?
An insufficient entropy vulnerability caused by the improper use of a randomness function with low entropy for web authentication tokens generation was found in the Zyxel GS1900 series switch firmware. This vulnerability could allow a LAN-based attacker to guess a valid session token if multiple authenticated sessions are alive.
What versions are vulnerable—and what should you do?
After a thorough investigation, we have identified the vulnerable products that are within their vulnerability support period, with their firmware patches shown in the table below.
| Affected model | Affected version | Patch availability |
|---|---|---|
| GS1900-8 | V2.80(AAHH.0)C0 | V2.80(AAHH.1)C0 |
| GS1900-8HP | V2.80(AAHI.0)C0 | V2.80(AAHI.1)C0 |
| GS1900-10HP | V2.80(AAZI.0)C0 | V2.80(AAZI.1)C0 |
| GS1900-16 | V2.80(AAHJ.0)C0 | V2.80(AAHJ.1)C0 |
| GS1900-24 | V2.80(AAHL.0)C0 | V2.80(AAHL.1)C0 |
| GS1900-24E | V2.80(AAHK.0)C0 | V2.80(AAHK.1)C0 |
| GS1900-24EP | V2.80(ABTO.0)C0 | V2.80(ABTO.1)C0 |
| GS1900-24HPv2 | V2.80(ABTP.0)C0 | V2.80(ABTP.1)C0 |
| GS1900-48 | V2.80(AAHN.0)C0 | V2.80(AAHN.1)C0 |
| GS1900-48HPv2 | V2.80(ABTQ.0)C0 | V2.80(ABTQ.1)C0 |
Got a question?
Please contact your local service rep or visit Zyxel’s Community for further information or assistance.
Acknowledgment
Thanks to Steinar H. Gunderson for reporting the issue to us.
Revision history
2024-9-10: Initial release.