{"id":"CVE-2026-44328","aliases":["GHSA-p9mg-74mg-cwwr","GO-2026-5537"],"url":"https://o3.security/vulnerability/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.","published":"2026-05-27T15:39:44.153Z","modified":"2026-08-07T11:51:10.235652463Z","cvss":{"score":8.2,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/free5gc/smf","fixedVersion":"1.4.3"}],"fix":{"url":"https://github.com/free5gc/smf/commit/b57bc48081c3d3a2f333d02eb78e4fd31a120deb","label":"free5gc/smf@b57bc48"},"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"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T11:51:10.235652463Z"}}