TI-2025-01490 Aliases CVE-2025-1731 GHSA-2w3x-653c-q4pc

Incorrect permission assignment in Zyxel USG FLEX H series uOS firmware

HIGH 69CWE-732Published 2025-04-22 · Updated 2026-02-26

Key facts

Attack vector: Local
Privileges required: Low
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

An incorrect permission assignment vulnerability in the PostgreSQL commands of the Zyxel USG FLEX H series uOS firmware versions from V1.20 through V1.31 could allow an authenticated local attacker with low privileges to gain access to the Linux shell and escalate their privileges by crafting malicious scripts or modifying system configurations with administrator-level access through a stolen token. Modifying the system configuration is only possible if the administrator has not logged out and the token remains valid.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00951 61st 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: Poc
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	USG FLEX H series uOS firmware	from V1.20 through V1.31	—	No fix listed	CNA

USG FLEX H series uOS firmware VendorZyxel Affected from V1.20 through V1.31 Fixed in — No fix listed CNA

CPE configurations NVD · 9

CPE	Versions	Role	Vendor
cpe:2.3:o:zyxel:uos::::::::	1.20 to before 1.32	Vulnerable	Zyxel
cpe:2.3:h:zyxel:usg_flex_100h:-:::::::*	not specified by NVD	Running on	Zyxel
cpe:2.3:h:zyxel:usg_flex_100hp:-:::::::*	not specified by NVD	Running on	Zyxel
cpe:2.3:h:zyxel:usg_flex_200h:-:::::::*	not specified by NVD	Running on	Zyxel
cpe:2.3:h:zyxel:usg_flex_200hp:-:::::::*	not specified by NVD	Running on	Zyxel
cpe:2.3:h:zyxel:usg_flex_500h:-:::::::*	not specified by NVD	Running on	Zyxel
cpe:2.3:h:zyxel:usg_flex_50h:-:::::::*	not specified by NVD	Running on	Zyxel
cpe:2.3:h:zyxel:usg_flex_50hp:-:::::::*	not specified by NVD	Running on	Zyxel
cpe:2.3:h:zyxel:usg_flex_700h:-:::::::*	not specified by NVD	Running on	Zyxel

cpe:2.3:o:zyxel:uos:*:*:*:*:*:*:*:* Versions 1.20 to before 1.32 Vulnerable ·Zyxel
cpe:2.3:h:zyxel:usg_flex_100h:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
cpe:2.3:h:zyxel:usg_flex_100hp:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
cpe:2.3:h:zyxel:usg_flex_200h:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
cpe:2.3:h:zyxel:usg_flex_200hp:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
cpe:2.3:h:zyxel:usg_flex_500h:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
cpe:2.3:h:zyxel:usg_flex_50h:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
cpe:2.3:h:zyxel:usg_flex_50hp:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
cpe:2.3:h:zyxel:usg_flex_700h:-:*:*:*:*:*:*:* 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 · 2025-04-22
Zyxel USG FLEX H series uOS firmware — zyxel.com/global/en/support/security-advisories/zyxel-secur…
2 records Highest priority Priority HIGH 1 HIGH, 1 LOW
Other records, highest priority first
- TI-2025-01491 Improper privilege management in Zyxel USG FLEX H series uOS firmwarePriority LOW 31
Show all 2 records → Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2025-1731
2026-10-03 Alias added: GHSA-2w3x-653c-q4pc

References

Advisory 1

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-incorrect-permission-assignment-and-improper-privilege-management-vulnerabilities-in-usg-flex-h-series-firewalls-04-22-2025

TI-2023-05872 OS command injection in Zyxel ATP series firmware CVSS 3.1HIGH 7.2
TI-2024-08978 Insufficiently protected credentials in Zyxel USG FLEX H series uOS firmware CVSS 3.1HIGH 7.8
TI-2025-01491 Improper privilege management in Zyxel USG FLEX H series uOS firmware CVSS 3.1MEDIUM 6.7
TI-2023-05873 A format string vulnerability in Zyxel ATP series firmware versions from 4.32 through… CVSS 3.1MEDIUM 6.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences