Zyxel security advisory for multiple vulnerabilities of firewalls, AP controllers, and Aps
Zyxel is aware of multiple vulnerabilities reported by security consultancies and advises users to install the applicable firmware updates for optimal protection.
What are the vulnerabilities?
A cross-site scripting vulnerability was identified in the CGI program of some firewall versions that could allow an attacker to obtain some information stored in the user’s browser, such as cookies or session tokens, via a malicious script.
Multiple improper input validation flaws were identified in some CLI commands of some firewall, AP controller, and AP versions that could allow a local authenticated attacker to cause a buffer overflow or a system crash via a crafted payload.
A command injection vulnerability in the "packet-trace" CLI command of some firewall, AP controller, and AP versions could allow a local authenticated attacker to execute arbitrary OS commands by including crafted arguments to the command.
An authentication bypass vulnerability caused by the lack of a proper access control mechanism has been found in the CGI program of some firewall versions. The flaw could allow an attacker to downgrade from two-factor authentication to one-factor authentication via an IPsec VPN client.
What versions are vulnerable—and what should you do?
After a thorough investigation, we’ve identified the vulnerable products that are within their vulnerability support period and released patches to address the CVEs, as shown in the tables below.
Table 1. Firewalls affected by CVE-2022-0734, CVE-2022-26531, CVE-2022-26532, and CVE-2022-0910
|Firewall||Affected version||Patch availability|
|USG/ZyWALL||ZLD V4.35~V4.70||ZLD V4.09~V4.71||ZLD V4.09~V4.71||ZLD V4.32~V4.71||ZLD V4.72|
|USG FLEX||ZLD V4.50~V5.20||ZLD V4.50~V5.21||ZLD V4.50~V5.21||ZLD V4.50~V5.21||ZLD V5.30|
|ATP||ZLD V4.35~V5.20||ZLD V4.32~V5.21||ZLD V4.32~V5.21||ZLD V4.32~V5.21||ZLD V5.30|
|VPN||ZLD V4.35~V5.20||ZLD V4.30~V5.21||ZLD V4.30~V5.21||ZLD V4.32~V5.21||ZLD V5.30|
|NSG||Not affected||V1.00~V1.33 Patch 4||V1.00~V1.33 Patch 4||Not affected||V1.33 Patch 5*|
*Available in middle of Jun.
Table 2. AP controllers affected by CVE-2022-26531 and CVE-2022-26532
|AP Controller||Affected version||Patch availability|
|CVE-2022-26531 and CVE-2022-26532|
|NXC2500||6.10(AAIG.3) and earlier||Hotfix by request**|
|NXC5500||6.10(AAOS.3) and earlier||Hotfix by request**|
Table 3. APs affected by CVE-2022-26531 and CVE-2022-26532
|AP||Affected version||Patch availability|
|CVE-2022-26531 and CVE-2022-26532|
|NAP203||6.25(ABFA.7) and earlier||6.25(ABFA.8)|
|NAP303||6.25(ABEX.7) and earlier||6.25(ABEX.8)|
|NAP353||6.25(ABEY.7) and earlier||6.25(ABEY.8)|
|NWA50AX||6.25(ABYW.5) and earlier||6.25(ABYW.8)|
|NWA55AXE||6.25(ABZL.5) and earlier||6.25(ABZL.8)|
|NWA90AX||6.27(ACCV.2) and earlier||6.27(ACCV.3)|
|NWA110AX||6.30(ABTG.2) and earlier||6.30(ABTG.3)|
|NWA210AX||6.30(ABTD.2) and earlier||6.30(ABTD.3)|
|NWA1123-AC-HD||6.25(ABIN.6) and earlier||6.25(ABIN.8)|
|NWA1123-AC-PRO||6.25(ABHD.7) and earlier||6.25(ABHD.8)|
|NWA1123ACv3||6.30(ABVT.2) and earlier||6.30(ABVT.3)|
|NWA1302-AC||6.25(ABKU.6) and earlier||6.25(ABKU.8)|
|NWA5123-AC-HD||6.25(ABIM.6) and earlier||6.25(ABIM.8)|
|WAC500H||6.30(ABWA.2) and earlier||6.30(ABWA.3)|
|WAC500||6.30(ABVS.2) and earlier||6.30(ABVS.3)|
|WAC5302D-S||6.10(ABFH.10) and earlier||Hotfix by request**|
|WAC5302D-Sv2||6.25(ABVZ.6) and earlier||6.25(ABVZ.8)|
|WAC6103D-I||6.25(AAXH.7) and earlier||6.25(AAXH.8)|
|WAC6303D-S||6.25(ABGL.6) and earlier||6.25(ABGL.8)|
|WAC6502D-E||6.25(AASD.7) and earlier||6.25(AASD.8)|
|WAC6502D-S||6.25(AASE.7) and earlier||6.25(AASE.8)|
|WAC6503D-S||6.25(AASF.7) and earlier||6.25(AASF.8)|
|WAC6553D-E||6.25(AASG.7) and earlier||6.25(AASG.8)|
|WAC6552D-S||6.25(ABIO.7) and earlier||6.25(ABIO.8)|
|WAX510D||6.30(ABTF.2) and earlier||6.30(ABTF.3)|
|WAX610D||6.30(ABTE.2) and earlier||6.30(ABTE.3)|
|WAX630S||6.30(ABZD.2) and earlier||6.30(ABZD.3)|
|WAX650S||6.30(ABRM.2) and earlier||6.30(ABRM.3)|
**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 forum for further information or assistance.
Thanks to the following security consultancies for reporting the issues to us:
- Riccardo Krauter at Soter IT Security for CVE-2022-0734
- HN Security for CVE-2022-26531 and CVE-2022-26532
- Ascend PC for CVE-2022-0910
2022-05-24: Initial release
2022-05-27: Updated NSG’s patch schedule