Vulnerability · Published Feb 23, 2026 · Assigned by GitHub_M
CVE-2025-69251free5GC has Improper Input Validation in UDM, Leading to Information Exposure
Medium 6.6
In plain English
A medium-severity improper input validation in udm from free5gc. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities).
Official description
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.
Affected products (as reported)
Weakness: CWE-20 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U
References
- https://github.com/free5gc/free5gc/security/advisories/GHSA-pwxh-4qh4-hgpq x_refsource_CONFIRM
- https://github.com/free5gc/free5gc/issues/751 x_refsource_MISC
- https://github.com/free5gc/free5gc/issues/76 x_refsource_MISC
- https://github.com/free5gc/udm/commit/504b14458d156558b3c0ade7107b86b3d5e72998 x_refsource_MISC