free5GC has Improper Input Validation in UDM, Leading to Information Exposure
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
free5gc UDM provides Unified Data Management (UDM) for free5GC, an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, remote attackers can inject control characters (e.g., %00) into the ueId parameter, triggering internal URL parsing errors (net/url: invalid control character). This exposes system implementation details and can aid in service fingerprinting. All deployments of free5GC using the UDM Nudm_UECM service may be affected. free5gc/udm pull request 76 contains a fix for the issue. No direct workaround is available at the application level. Applying the official patch is recommended.
Why it matters now
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
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2025-69251
References
More free5gc Udm vulnerabilities
- TI-2026-25617 free5GC UDM incorrectly returns 500 for empty supi path parameter in PATCH sdm-subscriptions reques CVSS 4.0HIGH 8.7
- TI-2026-25506 free5GC UDM DataChangeNotification Procedure Panic Due to Nil Pointer Dereference CVSS 4.0HIGH 8.7
- TI-2026-25507 free5GC UDM incorrectly returns 500 for empty supi path parameter in DELETE sdm-subscriptions request CVSS 4.0MEDIUM 6.9
- TI-2026-25616 free5GC UDM vulnerable to null byte injection in URL path parameters causing 500 Internal Server Error CVSS 4.0HIGH 8.7
- TI-2026-22024 free5GC has Improper Input Validation in UDM UEAU Service CVSS 4.0MEDIUM 6.6
- TI-2025-42704 free5GC has Null Pointer Dereference in UDM, Leading to Service Panic CVSS 4.0MEDIUM 6.6
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences