Missing authorization in Zyxel ATP series firmware
Priority MEDIUM 46CWE-862Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · High · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-862.
Summary
A missing authorization vulnerability in Zyxel ATP series firmware versions from V4.32 through V5.40, USG FLEX series firmware versions from V4.50 through V5.40, USG FLEX 50(W) series firmware versions from V4.16 through V5.40, and USG20(W)-VPN series firmware versions from V4.16 through V5.40 could allow a semi-authenticated attacker—who has completed only the first stage of the two-factor authentication (2FA) process—to view and download the system configuration from an affected device.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0546 92nd 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
- No
- Technical impact
- Total
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 | ATP series firmware | versions from V4.32 through V5.40 | — | No fix listed | CNA |
| Zyxel | USG FLEX series firmware | versions from V4.50 through V5.40 | — | No fix listed | CNA |
| Zyxel | USG FLEX 50(W) series firmware | versions from V4.16 through V5.40 | — | No fix listed | CNA |
| Zyxel | USG20(W)-VPN series firmware | versions from V4.16 through V5.40 | — | No fix listed | CNA |
- ATP series firmware VendorZyxel Affected versions from V4.32 through V5.40 Fixed in — No fix listed CNA
- USG FLEX series firmware VendorZyxel Affected versions from V4.50 through V5.40 Fixed in — No fix listed CNA
- USG FLEX 50(W) series firmware VendorZyxel Affected versions from V4.16 through V5.40 Fixed in — No fix listed CNA
- USG20(W)-VPN series firmware VendorZyxel Affected versions from V4.16 through V5.40 Fixed in — No fix listed CNA
CPE configurations NVD · 19
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:zyxel:zld:*:*:*:*:*:*:*:* | 4.32 to before 5.41 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:atp100:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:h:zyxel:atp100w:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:h:zyxel:atp200:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:h:zyxel:atp500:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:h:zyxel:atp700:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:h:zyxel:atp800:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:zld:*:*:*:*:*:*:*:* | 4.50 to before 5.41 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_100:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_100ax:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
- cpe:2.3:o:zyxel:zld:*:*:*:*:*:*:*:* Versions 4.32 to before 5.41 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:atp100:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:h:zyxel:atp100w:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:h:zyxel:atp200:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:h:zyxel:atp500:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:h:zyxel:atp700:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:h:zyxel:atp800:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:zld:*:*:*:*:*:*:*:* Versions 4.50 to before 5.41 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_100:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_100ax:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
Show 9 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:h:zyxel:usg_flex_100w:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_200:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_50:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_500:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_50ax:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_700:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:zld:*:*:*:*:*:*:*:* | 4.16 to before 5.41 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:usg_20w-vpn:*:*:*:*:*:*:*:* | all versions | Running on | Zyxel |
| cpe:2.3:h:zyxel:usg_flex_50w:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
- cpe:2.3:h:zyxel:usg_flex_100w:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_200:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_50:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_500:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_50ax:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_700:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:zld:*:*:*:*:*:*:*:* Versions 4.16 to before 5.41 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:usg_20w-vpn:*:*:*:*:*:*:*:* Versions all versions Running on ·Zyxel
- cpe:2.3:h:zyxel:usg_flex_50w:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
Remediation
No fixed version listed by the sources yet.
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Advisory ·
Zyxel ATP series firmware, USG FLEX 50(W) series firmware and 2 more products — zyxel.com/global/en/support/security-advisories/zyxel-secur…
2 records Highest priority Priority MEDIUM 1 MEDIUM, 1 LOW
Other records, highest priority first
- TI-2025-07391 OS command injection in Zyxel ATP series firmwarePriority LOW 37
Timeline
- 2026-10-02 Threatist record created from CVE-2025-9133
- 2026-10-03 Alias added: GHSA-x59x-qc82-4w4p
More Zyxel Zld vulnerabilities
- TI-2024-10813 Path traversal in Zyxel ATP series firmware KEVCVSS 3.1CRITICAL 9.8
- TI-2020-15281 A stack-based buffer overflow in fbwifi_continue.cgi on Zyxel UTM and VPN series of… CVSS 3.1CRITICAL 9.8
- TI-2023-04062 Integer overflow in Zyxel ATP series firmware CVSS 3.1HIGH 7.5
- TI-2024-28064 NULL pointer dereference in Zyxel ATP series firmware CVSS 3.1HIGH 7.5
- TI-2024-28063 OS command injection in Zyxel ATP series firmware CVSS 3.1HIGH 8.1
- TI-2025-07391 OS command injection in Zyxel ATP series firmware CVSS 3.1HIGH 7.2
Sources
- CVE-2025-9133 · CVE Program
- CVE-2025-9133 · NVD
- FIRST EPSS
- GHSA-x59x-qc82-4w4p · 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