Vulnerability · Published May 27, 2026 · Assigned by GitHub_M
CVE-2026-42459free5GC: Improper Input Validation and Generation of Error Message Containing Sensitive Information in github.com/free5gc/udm
High 7.7
In plain English
A high-severity improper input validation in free5gc from free5gc. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 26% of all known vulnerabilities).
Official description
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, the free5GC UDM component fails to validate the supi path parameter in six GET handlers of the nudm-sdm (Subscriber Data Management) service. An unauthenticated attacker can inject control characters into the SUPI parameter, causing UDM to forward a malformed request to UDR and return a 500 Internal Server Error response that exposes internal infrastructure details. This vulnerability is fixed in 4.2.2.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/free5gc/udm | no fix listed | GHSA-585v-hcgf-jhfr |
| Go | github.com/free5gc/udm | no fix listed | GO-2026-5138 |
Affected products (as reported)
Weakness: CWE-20, CWE-209 · 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:P
References
- https://github.com/free5gc/free5gc/security/advisories/GHSA-585v-hcgf-jhfr x_refsource_CONFIRM