Description
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's PCF POST /npcf-policyauthorization/v1/app-sessions handler panics on a single authenticated request whose ascReqData.suppFeat == "1" (enabling traffic-routing feature negotiation) and whose medComponents entries supply an afAppId but NO AfRoutReq. The create path then calls provisioningOfTrafficRoutingInfo(smPolicy, appID, routeReq, ...) with routeReq == nil and dereferences routeReq.RouteToLocs (and other fields) without a nil check, causing runtime error: invalid memory address or nil pointer dereference. Gin recovery converts the panic into HTTP 500. This vulnerability is fixed in 4.2.2.
Affected products
free5gc: free5gc
References5
- github.com/free5gc/free5gc/security/advisories/GHSA-wwqh-7jm5-g… ExploitVendor Advisory
- github.com/free5gc/free5gc/security/advisories/GHSA-wwqh-7jm5-g… ExploitVendor Advisory
- github.com/free5gc/pcf/commit/508d70b8527a6c8c923179dad450ea01e… Patch
- github.com/free5gc/pcf/pull/65 Issue TrackingPatch
- github.com/free5gc/free5gc/issues/879 ExploitIssue Tracking
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 29 · as of 14 November 2026
- CWE
- CWE-476CWE-754
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