Description
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's UDR nudr-dr DELETE /subscription-data/{ueId}/{servingPlmnId}/ee-subscriptions/{subsId}/amf-subscriptions handler panics on a single authenticated request against a fresh UDR instance when the supplied ueId does not exist in UESubsCollection. The processor checks value, ok := udrSelf.UESubsCollection.Load(ueId) and sets a 404 USER_NOT_FOUND problem-details on the miss path, but execution continues and immediately runs value.(*udr_context.UESubsData) -- a Go type assertion on a nil interface, which panics with interface conversion: interface {} is nil, not *context.UESubsData. Gin recovery converts the panic into HTTP 500, but the endpoint remains repeatedly panicable. This vulnerability is fixed in 4.2.2.
Affected products
free5gc: free5gc
References6
- github.com/free5gc/free5gc/security/advisories/GHSA-jqfc-gwj5-3… ExploitVendor Advisory
- github.com/free5gc/free5gc/security/advisories/GHSA-jqfc-gwj5-3… ExploitVendor Advisory
- github.com/free5gc/udr/commit/8a1d3c63be99d378806d771f086ff32f1… Patch
- github.com/free5gc/udr/pull/60 Issue TrackingPatch
- github.com/free5gc/free5gc/issues/920 ExploitIssue Tracking
- github.com/free5gc/free5gc/issues/920 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: 37 · as of 14 November 2026
- CWE
- CWE-704CWE-754
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