CVE-2026-44325: free5GC NRF type confusion in OAuth2 token endpoint

CVE-2026-44325 · Severity: high · CVSS 7.5 · Published 2026-05-27

A vulnerability in the free5GC Network Repository Function (NRF) allows an unauthenticated attacker to cause a service error by sending a specially crafted request to the token issuance endpoint. The NRF is a core component of 5G networks used for service discovery and authorization. While the system automatically recovers from these errors, a sustained attack could degrade performance, increase processing costs, and flood system logs with diagnostic data.

Technologies: free5GC NRF, github.com/free5gc/nrf (Go). Vendors: free5GC, Go.

Quick answers

Is CVE-2026-44325 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-44325 being exploited in the wild.
How severe is CVE-2026-44325?
High severity, with a CVSS score of 7.5, published 27 May 2026.
Which products and versions are affected?
free5GC NRF < 1.4.3, <= 4.2.1; github.com/free5gc/nrf (Go) < 1.4.3, SEMVER:introduced=0,fixed=1.4.3.
Is there a fix for CVE-2026-44325?
Yes. github.com/free5gc/nrf (Go): upgrade to 1.4.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-44325 attacked?
It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-44325?
Check whether you run free5GC NRF or github.com/free5gc/nrf (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • github.com/free5gc/nrf (Go): upgrade to 1.4.3 or later
    go get github.com/free5gc/nrf@v1.4.3

Technical details

A type-confusion vulnerability (CWE-843) exists in the `POST /oauth2/token` handler within `NFs/nrf/internal/sbi/api_accesstoken.go`. The parser uses Go reflection to map form-encoded body fields to the `models.NrfAccessTokenAccessTokenReq` struct but fails to validate that the input types match the destination field types. Specifically, it attempts to use `reflect.Value.Set()` to assign a `*models.PlmnId` type to fields expecting slices or different pointer types (e.g., `[]models.PlmnId`, `[]string`), leading to a runtime panic. While the Gin web framework catches these panics to prevent a full process crash, an unauthenticated attacker can repeatedly trigger this expensive failure path to cause resource exhaustion and log pollution. The issue is fixed in version 1.4.3.

Affected products

  • free5GC nrf < 1.4.3

Identifiers

  • CVE-2026-44325
  • GHSA-f8qv-7x5w-qr48
  • GO-2026-5349

Timeline

  • 2026-03-22: other: Vulnerability validated in lab environment
  • 2026-05-07: advisory: GitHub Advisory published
  • 2026-05-08: disclosed: Public disclosure

References

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