Zyxel security advisory for multiple vulnerabilities in firewalls and APs
CVEs: CVE-2023-6397, CVE-2023-6398, CVE-2023-6399, CVE-2023-6764
Summary
Zyxel has released patches addressing multiple vulnerabilities in some firewall and access point (AP) versions. Users are advised to install the patches for optimal protection.
What are the vulnerabilities?
CVE-2023-6397
A null pointer dereference vulnerability in some firewall versions could allow a LAN-based attacker to cause denial-of-service (DoS) conditions by downloading a crafted RAR compressed file onto a LAN-side host if the firewall has the “Anti-Malware” feature enabled.
CVE-2023-6398
A post-authentication command injection vulnerability in the file upload binary in some firewall and AP versions could allow an authenticated attacker with administrator privileges to execute some operating system (OS) commands on an affected device via FTP.
CVE-2023-6399
A format string vulnerability in some firewall versions could allow an authenticated IPSec VPN user to cause DoS conditions against the “deviceid” daemon by sending a crafted hostname to an affected device if it has the “Device Insight” feature enabled.
CVE-2023-6764
A format string vulnerability in a function of the IPSec VPN feature in some firewall versions could allow an attacker to achieve unauthorized remote code execution by sending a sequence of specially crafted payloads containing an invalid pointer; however, such an attack would require detailed knowledge of an affected device’s memory layout and configuration.
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 and released updates to address the vulnerabilities, as shown in the following tables.
Table 1. Firewalls affected by CVE-2023-6397, CVE-2023-6398, CVE-2023-6399, and CVE-2023-6764
| Firewall series | Affected version | Patch availability | |||
|---|---|---|---|---|---|
| CVE-2023-6397 | CVE-2023-6398 | CVE-2023-6399 | CVE-2023-6764 | ||
| ATP | ZLD V4.32 to V5.37 Patch 1 | ZLD V4.32 to V5.37 Patch 1 | ZLD V5.10 to V5.37 Patch 1 | ZLD V4.32 to V5.37 Patch 1 | ZLD V5.37 Patch 2 |
| USG FLEX | ZLD V4.50 to V5.37 Patch 1 | ZLD V4.50 to V5.37 Patch 1 | ZLD V5.10 to V5.37 Patch 1 | ZLD V4.50 to V5.37 Patch 1 | ZLD V5.37 Patch 2 |
| USG FLEX 50(W)/USG20(W)-VPN | Not affected | ZLD V4.16 to V5.37 Patch 1 | ZLD V5.10 to V5.37 Patch 1 | ZLD V4.16 to V5.37 Patch 1 | ZLD V5.37 Patch 2 |
| USG FLEX H | Not affected | uOS V1.10 to V1.10 Patch 1 | uOS V1.10 to V1.10 Patch 1 | Not affected | Hotfix is available* Standard patch uOS V1.20 in April 2024 |
Table 2. APs affected by CVE-2023-6398
| AP model | Affected version | Patch availability |
|---|---|---|
| NWA50AX | 6.29(ABYW.3) and earlier | 6.29(ABYW.4) |
| NWA55AXE | 6.29(ABZL.3) and earlier | 6.29(ABZL.4) |
| NWA90AX | 6.29(ACCV.3) and earlier | 6.29(ACCV.4) |
| NWA110AX | 6.65(ABTG.1) and earlier | 6.70(ABTG.2) |
| NWA210AX | 6.65(ABTD.1) and earlier | 6.70(ABTD.2) |
| NWA220AX-6E | 6.65(ACCO.1) and earlier | 6.70(ACCO.1) |
| NWA1123ACv3 | 6.65(ABVT.1) and earlier | 6.70(ABVT.1) |
| WAC500 | 6.65(ABVS.1) and earlier | 6.70(ABVS.1) |
| WAC500H | 6.65(ABWA.1) and earlier | 6.70(ABWA.1) |
| WAX300H | 6.60(ACHF.1) and earlier | 6.70(ACHF.1) |
| WAX510D | 6.65(ABTF.1) and earlier | 6.70(ABTF.2) |
| WAX610D | 6.65(ABTE.1) and earlier | 6.70(ABTE.2) |
| WAX620D-6E | 6.65(ACCN.1) and earlier | 6.70(ACCN.1) |
| WAX630S | 6.65(ABZD.1) and earlier | 6.70(ABZD.2) |
| WAX640S-6E | 6.65(ACCM.1) and earlier | 6.70(ACCM.1) |
| WAX650S | 6.65(ABRM.1) and earlier | 6.70(ABRM.2) |
| WAX655E | 6.65(ACDO.1) and earlier | 6.70(ACDO.1) |
| WBE660S | 6.65(ACGG.1) and earlier | 6.70(ACGG.2) |
| NWA50AX-PRO | 6.65(ACGE.1) and earlier | Hotfix is available upon request* Standard patch 6.80(ACGE.0) in July 2024 |
| NWA90AX-PRO | 6.65(ACGF.1) and earlier | Hotfix is available upon request* Standard patch 6.80(ACGF.0) in July 2024 |
*Please reach out to your local Zyxel support team for the file.
Got a question?
Please contact your local service rep or visit Zyxel’s Community for further information or assistance.
Acknowledgment
Thanks to Lays and atdog from TRAPA Security for reporting the issues to us.
Revision history
2024-2-20: Initial release
2024-2-21: Updated the affected model list and patch availability