{"id":"CVE-2026-18838","kind":"vulnerability","aliases":["CVE-2026-18838"],"related":[],"title":"IBM API Connect 12.1: unauthenticated remote caller can impersonate users and change API configurations","description":"IBM API Connect 12.1.0.0 through 12.1.1.2 could allow a remote attacker to obtain sensitive information and modify API configurations due to improper authentication. Identity information supplied in requests is not sufficiently verified, which could allow a caller to impersonate another user.","summary":"IBM API Connect V12 OnPrem v12.1.0.0 to v12.1.1.2 does not sufficiently verify identity information supplied in requests (CWE-290). IBM rates it CVSS 9.4 with no privileges required: a remote attacker can impersonate another user, read sensitive information and modify API configurations. Fixed in v12.1.1.3; IBM lists no workarounds.","severity":"critical","cvss":9.4,"epss":null,"exploited":false,"exploited_at":null,"products":[{"name":"IBM API Connect V12 OnPrem","fixed":["12.1.1.3"],"affected":">= 12.1.0.0, <= 12.1.1.2","ecosystem":"vendor"}],"ecosystems":[],"tags":["api-gateway","ibm-api-connect","on-prem","self-hosted","vendor"],"not_affected_if":["other-versions","v12.1.1.3-or-later"],"how_to_check":"Check your API Connect V12 OnPrem version. v12.1.0.0 through v12.1.1.2 is affected; v12.1.1.3 or later is fixed. The 10.0.8.x line is not listed for this CVE in this bulletin; also check other API Connect lines against their own IBM bulletins.","fix":"Upgrade IBM API Connect V12 OnPrem to v12.1.1.3 (Fix Central: https://www.ibm.com/support/pages/node/7290205). IBM lists no workarounds or mitigations.","status":"open","published_at":"2026-11-07T05:18:59+00:00","first_seen_at":"2026-11-07T05:46:08+00:00","triaged_at":"2026-11-07T05:48:33+00:00","updated_at":"2026-11-07T05:49:58+00:00","category":"vendor","confidence":0.9,"triage":{"at":"2026-11-07T05:48:33Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"internet","title":"IBM API Connect: weak identity checks let attackers impersonate users","impact":"high","summary":"IBM API Connect versions 12.1.0.0 through 12.1.1.2 do not sufficiently verify the identity information in requests. A remote attacker can impersonate another user, read sensitive information and change API configurations.","audience":"businesses","category":"vendor","nicknames":[],"who_cares":["ibm-api-connect","api-gateway"],"confidence":0.6,"fix_status":"unknown","needs_auth":"unknown","worst_case":"remote caller impersonates users and changes API configurations","analyst_note":"Find IBM's security bulletin for CVE-2026-18838 to confirm the fixed version and whether a remote caller needs credentials.","how_to_check":"- Check the installed API Connect version against the affected range `12.1.0.0` to `12.1.1.2`\n- unknown","plain_action":"","needs_analyst":true,"not_affected_if":["other-versions"],"who_is_affected":"Organizations running IBM API Connect 12.1.0.0 through 12.1.1.2 are affected, since the flaw lets remote callers pass as other users. Teams on other versions or not running API Connect can skip it. The sources do not say which deployment settings are required.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"critical"},"cost_usd":0.000669,"input_tokens":4230,"output_tokens":492,"severity_before":"critical"},"analyst_status":"done","analyst_note":"Find IBM's security bulletin for CVE-2026-18838 to confirm the fixed version and whether a remote caller needs credentials.","search":"'-18838':17A,20A '-2026':16A,19A '-290':58B '12.1':4A '12.1.0.0':92C '12.1.1.2':94C '9.4':63B 'allow':96C,123C 'anoth':73B,128C 'api':2A,13A,22A,27B,31B,41B,80B,90C,106C 'api-gateway':26B 'attack':70B,99C 'authent':111C 'caller':7A,125C 'chang':12A 'configur':14A,81B,107C 'connect':3A,23A,32B,42B,91C 'could':95C,122C 'cve':15A,18A 'cvss':62B 'cwe':57B 'due':108C 'fix':82B 'gateway':28B 'host':38B 'ibm':1A,21A,30B,40B,59B,85B,89C 'ibm-api-connect':29B 'ident':52B,112C 'imperson':9A,72B,127C 'improp':110C 'inform':53B,77B,103C,113C 'list':86B 'modifi':79B,105C 'obtain':101C 'on-prem':33B 'onprem':25A,44B 'prem':35B 'privileg':66B 'rate':60B 'read':75B 'remot':6A,69B,98C 'request':56B,116C 'requir':67B 'self':37B 'self-host':36B 'sensit':76B,102C 'suffici':50B,119C 'suppli':54B,114C 'unauthent':5A 'user':10A,74B,129C 'v12':24A,43B 'v12.1.0.0':45B 'v12.1.1.2':47B 'v12.1.1.3':84B 'vendor':39B 'verifi':51B,120C 'workaround':88B","nicknames":[],"mitigations":[],"who_affected":"Teams running self-managed IBM API Connect V12 OnPrem v12.1.0.0 through v12.1.1.2 are affected. IBM's CVSS vector shows it is reachable over the network with no credentials or user interaction. Teams on v12.1.1.3 or later can skip it; the bulletin lists no other API Connect versions or hosted offerings for this CVE.","tier":"B","verified":{"fix":{"at":"2026-11-07T05:49:58Z","by":"analyst","doc":"https://www.ibm.com/support/pages/security-bulletin-multiple-vulnerabilities-ibm-api-connect-39","run_id":1960},"products":{"at":"2026-11-07T05:49:58Z","by":"analyst","doc":"https://www.ibm.com/support/pages/security-bulletin-multiple-vulnerabilities-ibm-api-connect-39","run_id":1960},"mitigations":{"at":"2026-11-07T05:49:58Z","by":"analyst","doc":"https://www.ibm.com/support/pages/security-bulletin-multiple-vulnerabilities-ibm-api-connect-39","run_id":1960},"workarounds":{"at":"2026-11-07T05:49:58Z","by":"analyst","doc":"https://www.ibm.com/support/pages/security-bulletin-multiple-vulnerabilities-ibm-api-connect-39","run_id":1960},"how_to_check":{"at":"2026-11-07T05:49:58Z","by":"analyst","doc":"https://www.ibm.com/support/pages/security-bulletin-multiple-vulnerabilities-ibm-api-connect-39","run_id":1960},"who_affected":{"at":"2026-11-07T05:49:58Z","by":"analyst","doc":"https://www.ibm.com/support/pages/security-bulletin-multiple-vulnerabilities-ibm-api-connect-39","run_id":1960}},"analyst_revisit_at":null,"fix_status":"available","audience":"businesses","plain_action":null,"pkeys":["apiconnectv12onprem","ibmapiconnectv12onprem"],"ptokens":["api","connect","ibm","onprem","v12"],"labels":["apigateway","critical","ibmapiconnect","onprem","selfhosted","vendor"],"campaign_type":null,"search_a":"'-18838':17A,20A '-2026':16A,19A '12.1':4A 'api':2A,13A,22A 'caller':7A 'chang':12A 'configur':14A 'connect':3A,23A 'cve':15A,18A 'ibm':1A,21A 'imperson':9A 'onprem':25A 'remot':6A 'unauthent':5A 'user':10A 'v12':24A","search_b":"'-290':58B '9.4':63B 'anoth':73B 'api':27B,31B,41B,80B 'api-gateway':26B 'attack':70B 'configur':81B 'connect':32B,42B 'cvss':62B 'cwe':57B 'fix':82B 'gateway':28B 'host':38B 'ibm':30B,40B,59B,85B 'ibm-api-connect':29B 'ident':52B 'imperson':72B 'inform':53B,77B 'list':86B 'modifi':79B 'on-prem':33B 'onprem':44B 'prem':35B 'privileg':66B 'rate':60B 'read':75B 'remot':69B 'request':56B 'requir':67B 'self':37B 'self-host':36B 'sensit':76B 'suffici':50B 'suppli':54B 'user':74B 'v12':43B 'v12.1.0.0':45B 'v12.1.1.2':47B 'v12.1.1.3':84B 'vendor':39B 'verifi':51B 'workaround':88B","search_c":"'12.1.0.0':92C '12.1.1.2':94C 'allow':96C,123C 'anoth':128C 'api':90C,106C 'attack':99C 'authent':111C 'caller':125C 'configur':107C 'connect':91C 'could':95C,122C 'due':108C 'ibm':89C 'ident':112C 'imperson':127C 'improp':110C 'inform':103C,113C 'modifi':105C 'obtain':101C 'remot':98C 'request':116C 'sensit':102C 'suffici':119C 'suppli':114C 'user':129C 'verifi':120C","first_public_at":"2026-11-07T05:18:59+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L","cvss_by":"psirt@us.ibm.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-18838","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-18838","severity":null,"published_at":"2026-11-07T05:18:59+00:00","modified_at":"2026-11-07T05:18:59+00:00","first_seen_at":"2026-11-07T05:46:08+00:00","fetched_at":"2026-11-07T05:46:08+00:00","note":null},{"source":"analyst","external_id":"CVE-2026-18838:1960","url":"https://www.ibm.com/support/pages/security-bulletin-multiple-vulnerabilities-ibm-api-connect-39","severity":null,"published_at":"2026-11-07T05:49:58+00:00","modified_at":"2026-11-07T05:49:58+00:00","first_seen_at":"2026-11-07T05:49:58+00:00","fetched_at":"2026-11-07T05:49:58+00:00","note":"Read IBM bulletin (-39): CVE-2026-18838 CWE-290, CVSS 9.4 AV:N/PR:N (no credentials), affects API Connect V12 OnPrem v12.1.0.0-v12.1.1.2, fix v12.1.1.3, workarounds: None. No exploitation or PoC seen.","cites":["https://www.ibm.com/support/pages/security-bulletin-multiple-vulnerabilities-ibm-api-connect-39"]}],"documents":[{"id":93149,"url":"https://www.ibm.com/support/pages/security-bulletin-multiple-vulnerabilities-ibm-api-connect-39","title":"IBM Security Bulletin: Multiple Vulnerabilities in IBM API Connect (v12.1.1.3)","kind":"advisory","source":"analyst","publisher":null,"text":null,"published_at":null,"relation":"advisory","confidence":null,"note":null}],"exploit_sources":[],"notice":"Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai"}