{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "free5gc",
          "vendor": "free5gc",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c= 1.4.4"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "free5GC is an open-source implementation of the 5G core network. In version 1.4.4 and earlier, the AUSF component stores per-subscriber authentication state in a global sync.Map named AUSFContext.UePool in internal/context/context.go, keyed only by SUPI. Every request handled by internal/sbi/processor/ue_authentication.go creates an AusfUeContext, and AddAusfUeContextToPool executes ausfContext.UePool.Store(ausfUeContext.Supi, ausfUeContext), unconditionally replacing the active context for that SUPI. An attacker with access to the AUSF SBI/N12 interface can send concurrent POST /nausf-auth/v1/ue-authentications requests for the same target SUPI, causing all attempts to share one logical authentication context URL while K_aut, XRES, and EapID are repeatedly overwritten. A valid EAP-AKA\u0027 response for an earlier challenge is then checked against the latest context, causing AT_MAC verification to fail and denying authentication to the selected subscriber while the request flood continues. No fixed version is available as of this review."
        }
      ],
      "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-362",
              "description": "CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization (\u0027Race Condition\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-28T22:23:41.923Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/free5gc/free5gc/security/advisories/GHSA-334q-h5g3-fpxv",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/free5gc/free5gc/security/advisories/GHSA-334q-h5g3-fpxv"
        }
      ],
      "source": {
        "advisory": "GHSA-334q-h5g3-fpxv",
        "discovery": "UNKNOWN"
      },
      "title": "free5GC AUSF authentication contexts can be overwritten by concurrent requests for the same SUPI"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-55784",
    "datePublished": "2026-08-28T22:23:41.923Z",
    "dateReserved": "2026-06-17T14:40:28.379Z",
    "dateUpdated": "2026-08-28T22:23:41.923Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}