Vulnerability Description
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without inbound OAuth2 middleware. On top of that, the DELETE /upi/v1/upNodesLinks/{upNodeRef} handler unconditionally dereferences upNode.UPF after the type-guarded async release, even though AN-typed nodes are constructed without a UPF object. As a result, a single unauthenticated DELETE /upi/v1/upNodesLinks/gNB1 request crashes the handler with a nil-pointer panic AND mutates the in-memory user-plane topology before panicking (the UpNodeDelete(upNodeRef) line runs first). This is an unauthenticated, state-mutating panic-DoS sink that an off-path network attacker can trigger by name against any AN entry. This vulnerability is fixed in 4.2.2.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Free5Gc | Free5Gc | < 4.2.2 |
Related Weaknesses (CWE)
References
- https://github.com/free5gc/free5gc/issues/905ExploitIssue Tracking
- https://github.com/free5gc/free5gc/security/advisories/GHSA-p9mg-74mg-cwwrExploitVendor Advisory
- https://github.com/free5gc/smf/commit/b57bc48081c3d3a2f333d02eb78e4fd31a120debPatch
- https://github.com/free5gc/smf/pull/199Issue TrackingPatch
- https://github.com/free5gc/free5gc/issues/905ExploitIssue Tracking
- https://github.com/free5gc/free5gc/security/advisories/GHSA-p9mg-74mg-cwwrExploitVendor Advisory
FAQ
What is CVE-2026-44328?
CVE-2026-44328 is a vulnerability with a CVSS score of 8.2 (HIGH). free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without inbound OAuth2 middleware. On top of that, the DELETE /upi/...
How severe is CVE-2026-44328?
CVE-2026-44328 has been rated HIGH with a CVSS base score of 8.2/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-44328?
Check the references section above for vendor advisories and patch information. Affected products include: Free5Gc Free5Gc.