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 contains a nil-pointer dereference reachable from a single authenticated request, after one preparatory authenticated EE-subscription create. The handler checks _, ok = UESubsData.EeSubscriptionCollection[subsId] and sets a 404 problem-details on the miss path, but then continues to UESubsData.EeSubscriptionCollection[subsId].AmfSubscriptionInfos -- dereferencing the same missing entry instead of returning. 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
References4
- github.com/free5gc/free5gc/security/advisories/GHSA-4rqf-grm6-v… ExploitVendor Advisory
- github.com/free5gc/udr/commit/8a1d3c63be99d378806d771f086ff32f1… Patch
- github.com/free5gc/udr/pull/60 Issue TrackingPatch
- github.com/free5gc/free5gc/issues/919 ExploitIssue Tracking
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: NVD
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-476
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