{"id":"CVE-2026-18668","kind":"vulnerability","aliases":["CVE-2026-18668"],"related":[],"title":"IBM Sterling File Gateway: remote attacker can force protocol downgrade via misconfiguration","description":"IBM Sterling File Gateway 6.2.1.0 through 6.2.1.2_1 and  6.2.2.0 - 6.2.2.1_1 could allow a remote attacker to perform protocol downgrade attacks due to a security misconfiguration.","summary":"IBM Sterling File Gateway versions 6.2.1.0 through 6.2.1.2_1 and 6.2.2.0 through 6.2.2.1_1 contain a security misconfiguration. A remote attacker can perform protocol downgrade attacks against the file transfer service.","severity":"medium","cvss":6.5,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["file-transfer","ibm-sterling","self-hosted","vendor"],"not_affected_if":["other-versions"],"how_to_check":"- Confirm the installed Sterling File Gateway version against the affected ranges 6.2.1.0 through 6.2.1.2_1 and 6.2.2.0 through 6.2.2.1_1","fix":null,"status":"open","published_at":"2026-11-08T18:17:04+00:00","first_seen_at":"2026-11-08T18:22:22+00:00","triaged_at":"2026-11-08T18:22:37+00:00","updated_at":"2026-11-08T18:22:37+00:00","category":"vendor","confidence":0.5,"triage":{"at":"2026-11-08T18:22:37Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"network","title":"IBM Sterling File Gateway: remote attacker can force protocol downgrade via misconfiguration","impact":"medium","summary":"IBM Sterling File Gateway versions 6.2.1.0 through 6.2.1.2_1 and 6.2.2.0 through 6.2.2.1_1 contain a security misconfiguration. A remote attacker can perform protocol downgrade attacks against the file transfer service.","audience":"businesses","category":"vendor","nicknames":[],"who_cares":["ibm-sterling","file-transfer","self-hosted"],"confidence":0.5,"fix_status":"unknown","needs_auth":"unknown","worst_case":"attacker forces weaker protocol, weakening transfer security","analyst_note":"Find the IBM security bulletin for CVE-2026-18668 to get the fixed version and the exact misconfiguration to check.","how_to_check":"- Confirm the installed Sterling File Gateway version against the affected ranges 6.2.1.0 through 6.2.1.2_1 and 6.2.2.0 through 6.2.2.1_1\n- unknown for the specific configuration setting to inspect; the sources do not say","plain_action":"","product_name":"","needs_analyst":true,"not_affected_if":["other-versions"],"who_is_affected":"Organizations running IBM Sterling File Gateway in the affected version ranges are exposed to protocol downgrade attacks via a misconfiguration. The sources do not name the specific setting or the required network position. Teams on other versions or without this product can skip it.","user_interaction":"unknown","product_ecosystem":"","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000748,"input_tokens":4572,"output_tokens":582,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-18668':15A,18A '-2026':14A,17A '1':37B,42B,67C,71C '6.2.1.0':34B,64C '6.2.1.2':36B,66C '6.2.2.0':39B,69C '6.2.2.1':41B,70C 'allow':73C 'attack':6A,49B,54B,76C,81C 'contain':43B 'could':72C 'cve':13A,16A 'downgrad':10A,53B,80C 'due':82C 'file':3A,20B,31B,57B,62C 'file-transf':19B 'forc':8A 'gateway':4A,32B,63C 'host':27B 'ibm':1A,23B,29B,60C 'ibm-sterl':22B 'misconfigur':12A,46B,86C 'perform':51B,78C 'protocol':9A,52B,79C 'remot':5A,48B,75C 'secur':45B,85C 'self':26B 'self-host':25B 'servic':59B 'sterl':2A,24B,30B,61C 'transfer':21B,58B 'vendor':28B 'version':33B 'via':11A","nicknames":[],"mitigations":[],"who_affected":"Organizations running IBM Sterling File Gateway in the affected version ranges are exposed to protocol downgrade attacks via a misconfiguration. The sources do not name the specific setting or the required network position. Teams on other versions or without this product can skip it.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["filetransfer","ibmsterling","medium","selfhosted","vendor"],"campaign_type":null,"search_a":"'-18668':15A,18A '-2026':14A,17A 'attack':6A 'cve':13A,16A 'downgrad':10A 'file':3A 'forc':8A 'gateway':4A 'ibm':1A 'misconfigur':12A 'protocol':9A 'remot':5A 'sterl':2A 'via':11A","search_b":"'1':37B,42B '6.2.1.0':34B '6.2.1.2':36B '6.2.2.0':39B '6.2.2.1':41B 'attack':49B,54B 'contain':43B 'downgrad':53B 'file':20B,31B,57B 'file-transf':19B 'gateway':32B 'host':27B 'ibm':23B,29B 'ibm-sterl':22B 'misconfigur':46B 'perform':51B 'protocol':52B 'remot':48B 'secur':45B 'self':26B 'self-host':25B 'servic':59B 'sterl':24B,30B 'transfer':21B,58B 'vendor':28B 'version':33B","search_c":"'1':67C,71C '6.2.1.0':64C '6.2.1.2':66C '6.2.2.0':69C '6.2.2.1':70C 'allow':73C 'attack':76C,81C 'could':72C 'downgrad':80C 'due':82C 'file':62C 'gateway':63C 'ibm':60C 'misconfigur':86C 'perform':78C 'protocol':79C 'remot':75C 'secur':85C 'sterl':61C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-08T18:17:04+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","cvss_by":"psirt@us.ibm.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-18668","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-18668","severity":null,"published_at":"2026-11-08T18:17:04+00:00","modified_at":"2026-11-08T18:17:04+00:00","first_seen_at":"2026-11-08T18:22:22+00:00","fetched_at":"2026-11-08T18:22:22+00:00","note":null}],"documents":[],"disclosures":[],"exploit_sources":[],"notice":"Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai"}