Vulnerability Description
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, PCF Npcf_SMPolicyControl missing authentication middleware allows unauthenticated access to SM policy handlers and disclosure of subscriber SUPI. In NewServer(), the smPolicyGroup route group is created and routes are applied without attaching the router authorization middleware. In contrast, other PCF service groups such as Npcf_PolicyAuthorization do attach RouterAuthorizationCheck before route registration. Because the middleware is missing, requests to the /npcf-smpolicycontrol/v1/sm-policies, /npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}, /npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}/update, and /npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}/delete endpoints can reach business logic even when no valid OAuth token is provided. This vulnerability is fixed in 4.2.2.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Free5Gc | Free5Gc | < 4.2.2 |
Related Weaknesses (CWE)
References
- https://github.com/free5gc/free5gc/issues/844ExploitIssue Tracking
- https://github.com/free5gc/free5gc/security/advisories/GHSA-6rgm-gr97-x3j5Issue TrackingVendor Advisory
- https://github.com/free5gc/pcf/commit/8c4d457cdf58bb239ee30e88c56b370b22073964Patch
- https://github.com/free5gc/pcf/pull/63Issue TrackingPatch
- https://github.com/free5gc/free5gc/issues/844ExploitIssue Tracking
- https://github.com/free5gc/free5gc/security/advisories/GHSA-6rgm-gr97-x3j5Issue TrackingVendor Advisory
FAQ
What is CVE-2026-42083?
CVE-2026-42083 is a vulnerability with a CVSS score of 8.2 (HIGH). free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, PCF Npcf_SMPolicyControl missing authentication middleware allows unauthenticated access to SM policy handlers and disc...
How severe is CVE-2026-42083?
CVE-2026-42083 has been rated HIGH with a CVSS base score of 8.2/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-42083?
Check the references section above for vendor advisories and patch information. Affected products include: Free5Gc Free5Gc.