{"id":"CVE-2026-44328","summary":"free5GC: SMF UPI DELETE /upi/v1/upNodesLinks/{ref} panics on AN-node deletion via nil UPF dereference; unauthenticated, state-mutating","details":"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.","aliases":["GHSA-p9mg-74mg-cwwr","GO-2026-5537"],"modified":"2026-08-12T03:51:44.167327307Z","published":"2026-05-27T15:39:44.153Z","related":["openSUSE-SU-2026:21483-1"],"database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-306","CWE-476","CWE-862"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44328.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44328.json"},{"type":"ADVISORY","url":"https://github.com/free5gc/free5gc/security/advisories/GHSA-p9mg-74mg-cwwr"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-44328"},{"type":"REPORT","url":"https://github.com/free5gc/free5gc/issues/905"},{"type":"FIX","url":"https://github.com/free5gc/smf/commit/b57bc48081c3d3a2f333d02eb78e4fd31a120deb"},{"type":"FIX","url":"https://github.com/free5gc/smf/pull/199"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/free5gc/free5gc","events":[{"introduced":"0"},{"fixed":"8b0f4445fc931638fb624463ce3572a203517679"}],"database_specific":{"cpe":"cpe:2.3:a:free5gc:free5gc:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"fixed":"4.2.2"}],"source":["AFFECTED_FIELD","CPE_RANGE"]}},{"type":"GIT","repo":"https://github.com/free5gc/smf","events":[{"introduced":"0"},{"fixed":"b57bc48081c3d3a2f333d02eb78e4fd31a120deb"}],"database_specific":{"source":"REFERENCES"}}],"versions":["v4.2.1","v4.2.0","v4.1.0","v4.0.1","v4.0.0","v3.4.5","v3.4.4","v3.4.3","v3.4.2","v3.4.1","v3.4.0","v3.3.0","v3.2.1","v3.2.0","v3.1.1","v3.1.0","v3.0.7","v3.0.6","v3.0.5","v1.4.2","v1.4.1","v1.4.0","v1.3.2","v1.3.1","v1.3.0","v1.2.7","v1.2.6","v1.2.5","v1.2.4","v1.2.3","v1.2.2","v1.2.1","v1.2.0","v1.1.1","v1.1.0","v1.0.2","v1.0.1","v1.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-44328.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H"}]}