CVE-2026-44322: free5GC: NEF 3gpp-pfd-management PATCH applications/{appId} panics on UDR access failure due to nil ProblemDetails dereference

Vulnerability summary

CVE-2026-44322 is a high (CVSS 7.5) NULL Pointer Dereference vulnerability in free5gc. EPSS estimates a 0.66% chance of exploitation in the next 30 days, higher than 50.7% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 27-05-2026
   PublishedVulnerability first disclosed.
2. 28-05-2026
   Last modifiedVulnerability information updated.

Description

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF PATCH /3gpp-pfd-management/v1/{afId}/transactions/{transId}/applications/{appId} handler panics with a nil-pointer dereference when the upstream UDR call fails AND the consumer wrapper returns err != nil together with a nil *ProblemDetails. The handler's errPfdData != nil branch builds its own problemDetailsErr correctly, but immediately after it reads problemDetails.Cause (the OTHER value, which is nil in this branch) and panics. Gin recovery converts the panic into HTTP 500, so a single PATCH against this endpoint returns 500 instead of the intended controlled error response whenever UDR access is failing. This vulnerability is fixed in 4.2.2.

• CWE-476NULL Pointer DereferenceThe product dereferences a pointer that it expects to be valid but is NULL.
• CWE-754Improper Check for Unusual or Exceptional ConditionsThe product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product.