free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, the AMF in Free5GC does not verify the UE Security Capabilities received in NGAP PathSwitchRequest messages against its locally stored values, as mandated by 3GPP TS 33.501 §6.7.3.1. A malicious gNB can overwrite the AMF's stored UE security capabilities with arbitrary values, which are then propagated in PathSwitchRequest Acknowledge messages and subsequent Handover Request messages. This leads to persistent handover denial-of-service for affected UEs. This vulnerability is fixed in 4.2.2.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://github.com/free5gc/free5gc/security/advisories/GHSA-77x9-rf64-92gv Exploit, Vendor Advisory
- https://github.com/free5gc/free5gc/security/advisories/GHSA-77x9-rf64-92gv Exploit, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 7.1 · free5gcNVD modified 2026-10-14 20:10
Affected (CPE criteria) 1
cpe:2.3:a:free5gc:free5gc:*:*:*:*:*:*:*:*
References 2
- https://github.com/free5gc/free5gc/security/advisories/GHSA-77x9-rf64-92gv Exploit, Vendor Advisory
- https://github.com/free5gc/free5gc/security/advisories/GHSA-77x9-rf64-92gv Exploit, Vendor Advisory