{"id":"CVE-2026-44321","state":"PUBLISHED","title":"free5GC: SMF UPI POST /upi/v1/upNodesLinks exits the SMF process on overlapping UE pools (unauthenticated, reachable Fatalf)","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. The POST /upi/v1/upNodesLinks create-or-update handler accepts attacker-controlled JSON and passes it directly into UpNodesFromConfiguration(), which calls logger.InitLog.Fatalf(...) on several validation failures. One confirmed path is the UE-IP-pool overlap check: a single unauthenticated POST that adds a new UPF whose pool overlaps an existing UPF terminates the entire SMF process (docker ps shows Exited (1)), not just the goroutine. This vulnerability is fixed in 4.2.2.","publishedAt":"2026-05-27T15:47:33.112Z","updatedAt":"2026-05-27T17:53:42.800Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["free5gc free5gc"],"affected":[{"vendor":"free5gc","product":"free5gc","versions":[{"version":"< 4.2.2","status":"affected"}]}],"references":["https://github.com/free5gc/free5gc/security/advisories/GHSA-44qj-cghf-9p97","https://github.com/free5gc/free5gc/issues/906","https://github.com/free5gc/smf/pull/203","https://github.com/free5gc/smf/commit/e0974e07ddab44a67d36a563cca383b2449e33e5"],"weaknesses":["CWE-306","CWE-617","CWE-862"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/44xxx/CVE-2026-44321.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-44321","state":"PUBLISHED","datePublished":"2026-05-27T15:47:33.112Z","dateUpdated":"2026-05-27T17:53:42.800Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-05T19:00:06.022Z"},"containers":{"cna":{"title":"free5GC: SMF UPI POST /upi/v1/upNodesLinks exits the SMF process on overlapping UE pools (unauthenticated, reachable Fatalf)","descriptions":[{"lang":"en","value":"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. The POST /upi/v1/upNodesLinks create-or-update handler accepts attacker-controlled JSON and passes it directly into UpNodesFromConfiguration(), which calls logger.InitLog.Fatalf(...) on several validation failures. One confirmed path is the UE-IP-pool overlap check: a single unauthenticated POST that adds a new UPF whose pool overlaps an existing UPF terminates the entire SMF process (docker ps shows Exited (1)), not just the goroutine. This vulnerability is fixed in 4.2.2."}],"affected":[{"vendor":"free5gc","product":"free5gc","versions":[{"version":"< 4.2.2","status":"affected"}]}],"references":[{"url":"https://github.com/free5gc/free5gc/security/advisories/GHSA-44qj-cghf-9p97","name":"https://github.com/free5gc/free5gc/security/advisories/GHSA-44qj-cghf-9p97","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/free5gc/free5gc/issues/906","name":"https://github.com/free5gc/free5gc/issues/906","tags":["x_refsource_MISC"]},{"url":"https://github.com/free5gc/smf/pull/203","name":"https://github.com/free5gc/smf/pull/203","tags":["x_refsource_MISC"]},{"url":"https://github.com/free5gc/smf/commit/e0974e07ddab44a67d36a563cca383b2449e33e5","name":"https://github.com/free5gc/smf/commit/e0974e07ddab44a67d36a563cca383b2449e33e5","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-306","lang":"en","description":"CWE-306: Missing Authentication for Critical Function","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-617","lang":"en","description":"CWE-617: Reachable Assertion","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-862","lang":"en","description":"CWE-862: Missing Authorization","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-05-27T15:47:33.112Z"},"source":{"advisory":"GHSA-44qj-cghf-9p97","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/free5gc/free5gc/security/advisories/GHSA-44qj-cghf-9p97","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-27T17:53:25.117261Z","id":"CVE-2026-44321","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-05-27T17:53:42.800Z"}}]}}}