Path traversal in Zyxel USG FLEX series firmware
Priority MEDIUM 40CWE-22Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA.
Summary
A path traversal vulnerability in the “account_print.cgi” CGI program of Zyxel USG FLEX series firmware versions 4.50 through 5.35, and VPN series firmware versions 4.30 through 5.35, which could allow a remote authenticated attacker with administrator privileges to execute unauthorized OS commands in the “tmp” directory by uploading a crafted file if the hotspot function were enabled.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01033 64th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Zyxel | USG FLEX series firmware | 4.50 through 5.35 | — | No fix listed | CNA |
| Zyxel | VPN series firmware | 4.30 through 5.35 | — | No fix listed | CNA |
- USG FLEX series firmware VendorZyxel Affected 4.50 through 5.35 Fixed in — No fix listed CNA
- VPN series firmware VendorZyxel Affected 4.30 through 5.35 Fixed in — No fix listed CNA
CPE configurations NVD · 22
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:zyxel:usg_flex_100_firmware:*:*:*:*:*:*:*:* | 4.50 – 5.35 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_100:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:usg_flex_100w_firmware:*:*:*:*:*:*:*:* | 4.50 – 5.35 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_100w:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:usg_flex_200_firmware:*:*:*:*:*:*:*:* | 4.50 – 5.35 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_200:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:usg_flex_50_firmware:*:*:*:*:*:*:*:* | 4.50 – 5.35 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_50:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:usg_flex_50w_firmware:*:*:*:*:*:*:*:* | 4.50 – 5.35 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_50w:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
- cpe:2.3:o:zyxel:usg_flex_100_firmware:*:*:*:*:*:*:*:* Versions 4.50 – 5.35 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_100:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:usg_flex_100w_firmware:*:*:*:*:*:*:*:* Versions 4.50 – 5.35 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_100w:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:usg_flex_200_firmware:*:*:*:*:*:*:*:* Versions 4.50 – 5.35 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_200:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:usg_flex_50_firmware:*:*:*:*:*:*:*:* Versions 4.50 – 5.35 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_50:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:usg_flex_50w_firmware:*:*:*:*:*:*:*:* Versions 4.50 – 5.35 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_50w:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
Show 12 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:zyxel:usg_flex_500_firmware:*:*:*:*:*:*:*:* | 4.50 – 5.35 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_500:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:usg_flex_700_firmware:*:*:*:*:*:*:*:* | 4.50 – 5.35 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_700:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:vpn100_firmware:*:*:*:*:*:*:*:* | 4.50 – 5.35 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:vpn100:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:vpn1000_firmware:*:*:*:*:*:*:*:* | 4.50 – 5.35 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:vpn1000:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:vpn300_firmware:*:*:*:*:*:*:*:* | 4.50 – 5.35 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:vpn300:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:vpn50_firmware:*:*:*:*:*:*:*:* | 4.50 – 5.35 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:vpn50:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
- cpe:2.3:o:zyxel:usg_flex_500_firmware:*:*:*:*:*:*:*:* Versions 4.50 – 5.35 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_500:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:usg_flex_700_firmware:*:*:*:*:*:*:*:* Versions 4.50 – 5.35 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_700:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:vpn100_firmware:*:*:*:*:*:*:*:* Versions 4.50 – 5.35 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:vpn100:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:vpn1000_firmware:*:*:*:*:*:*:*:* Versions 4.50 – 5.35 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:vpn1000:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:vpn300_firmware:*:*:*:*:*:*:*:* Versions 4.50 – 5.35 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:vpn300:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:vpn50_firmware:*:*:*:*:*:*:*:* Versions 4.50 – 5.35 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:vpn50:-:*:*:*:*:*:*:* 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-2023-22914
- 2026-10-03 Alias added: GHSA-3pc2-c878-63rj
References
More Zyxel Usg Flex 100 Firmware vulnerabilities
- TI-2023-16198 Buffer overflow in Zyxel ATP series firmware KEVCVSS 3.1CRITICAL 9.8
- TI-2023-16197 Buffer overflow in Zyxel ATP series firmware KEVCVSS 3.1CRITICAL 9.8
- TI-2023-13281 OS command injection in Zyxel ZyWALL/USG series firmware KEVCVSS 3.1CRITICAL 9.8
- TI-2020-17772 Firmware version 4.60 of Zyxel USG devices contains an undocumented account (zyfwp) with… KEVCVSS 3.1CRITICAL 9.8
- TI-2022-00268 Improper authentication in Zyxel USG/ZyWALL series firmware CVSS 3.1CRITICAL 9.8
- TI-2023-16200 OS command injection in Zyxel ATP series firmware CVSS 3.1HIGH 8.8
Sources
- CVE-2023-22914 · CVE Program
- CVE-2023-22914 · NVD
- FIRST EPSS
- GHSA-3pc2-c878-63rj · 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