free5GC is an open-source project for 5th generation (5G) mobile core networks. Versions up to and including 1.4.1 of free5GC's AMF service have a Buffer Overflow vulnerability leading to Denial of Service. Remote unauthenticated attackers can crash the AMF service by sending a specially crafted NAS Registration Request with a malformed 5GS Mobile Identity, causing complete denial of service for the 5G core network.
All deployments of free5GC using the AMF component may be affected. Pull request 43 of the free5gc/nas repo contains a fix. No direct workaround is available at the application level.
Applying the official patch is recommended.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
High
Complete denial of service
CVSS Vector v4.0
Weakness Type (CWE)
References 4
https://github.com/free5gc/free5gc/issues/747
security-advisories@github.com
https://github.com/free5gc/free5gc/security/advisories/GHSA-h6xc-8vvf-jcjp
security-advisories@github.com
https://github.com/free5gc/nas/commit/0329a7ac3f314f210366c1b3c33dc29eded4ac5f
security-advisories@github.com
https://github.com/free5gc/nas/pull/43
security-advisories@github.com