CVE-2026-27642
HIGH WAF: Medium
CVSS 7.5
Published: 2026-02-24
CWE-20
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 supi parameter, triggering internal URL parsing errors (net/url: invalid control character). This exposes system-level error details and can be used for service fingerprinting. All deployments of free5GC using the UDM Nudm_UEAU service may be affected. free5gc/udm pull request 75 contains a fix for the issue. No direct workaround is available at the application level. Applying the official patch is recommended.
WAF Coverage Analysis
Improper Input Validation
Medium WAF Coverage
OWASP: A03:2021 Injection
920xxx - Protocol Enforcement 941xxx - XSS / XXE 942xxx - SQL Injection
Affected Software
| Vendor | Product | Version |
|---|---|---|
| free5gc | udm | up to 1.4.1 |
References
- github.com (Exploit, Issue Tracking, Vendor Advisory)
- github.com (Vendor Advisory)
- github.com (Patch)
- github.com (Issue Tracking, Patch)