{"id":"CVE-2026-91421","kind":"vulnerability","aliases":["CVE-2026-91421"],"related":[],"title":"Oracle Siebel CRM Deployment: unauthenticated HTTP request can hang or crash server","description":"Vulnerability in the Siebel CRM Deployment product of Oracle Siebel CRM (component: Server Infrastructure).  Supported versions that are affected are 17.0-26.9. Difficult to exploit vulnerability allows unauthenticated attacker with network access via HTTP to compromise Siebel CRM Deployment.  Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of Siebel CRM Deployment. CVSS 3.1 Base Score 5.9 (Availability impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H).","summary":"Oracle Siebel CRM Deployment, Server Infrastructure component, versions 17.0 through 26.9, has a flaw reachable over HTTP without credentials. A remote attacker can repeatedly hang or crash the service, causing denial of service.","severity":"medium","cvss":5.9,"epss":0.00367,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["oracle","self-hosted","siebel-crm","vendor"],"not_affected_if":["unaffected-version"],"how_to_check":"- Identify Siebel CRM Deployment installs and their version: unknown\n- Confirm whether the Server Infrastructure component is exposed over HTTP to the network: unknown","fix":"- Apply the Oracle Critical Patch Update fix for Siebel CRM 17.0 to 26.9: unknown patch level in sources","status":"open","published_at":"2026-10-20T22:20:45+00:00","first_seen_at":"2026-10-23T21:57:26+00:00","triaged_at":"2026-10-25T04:08:09+00:00","updated_at":"2026-10-25T12:38:52+00:00","category":"vendor","confidence":0.6,"triage":{"at":"2026-10-25T04:08:09Z","model":"claude-haiku-5-5","output":{"fix":"- Apply the Oracle Critical Patch Update fix for Siebel CRM 17.0 to 26.9: unknown patch level in sources","reach":"network","title":"Oracle Siebel CRM Deployment: unauthenticated HTTP request can hang or crash server","impact":"low","summary":"Oracle Siebel CRM Deployment, Server Infrastructure component, versions 17.0 through 26.9, has a flaw reachable over HTTP without credentials. A remote attacker can repeatedly hang or crash the service, causing denial of service.","category":"vendor","nicknames":[],"who_cares":["oracle","siebel-crm","self-hosted"],"confidence":0.6,"needs_auth":"no","worst_case":"Remote denial of service: service hangs or repeatedly crashes","analyst_note":"Find Oracle's CPU advisory for CVE-2026-91421 to confirm patched versions and any configuration conditions.","how_to_check":"- Identify Siebel CRM Deployment installs and their version: unknown\n- Confirm whether the Server Infrastructure component is exposed over HTTP to the network: unknown","needs_analyst":true,"not_affected_if":["unaffected-version"],"who_is_affected":"Organizations running Oracle Siebel CRM Deployment in the affected version range 17.0 through 26.9 with HTTP reachable from the network. Sources do not say which deployment configurations are impacted, so the exact scope is unknown.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.000621,"input_tokens":3477,"output_tokens":546,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-2026':14A,17A '-26.9':81C '-91421':15A,18A '/av':134C '17.0':35B,80C '26.9':37B '3.1':124C,133C '5.9':127C 'abil':108C 'access':91C 'affect':78C 'allow':86C 'attack':48B,88C,100C 'avail':128C 'base':125C 'caus':56B,110C 'complet':117C 'compon':33B,71C 'compromis':95C 'crash':11A,53B,116C 'credenti':45B 'crm':3A,25B,29B,64C,70C,97C,121C 'cve':13A,16A 'cvss':123C,130C,132C 'denial':57B 'deploy':4A,30B,65C,98C,122C 'difficult':82C 'dos':118C 'exploit':84C 'flaw':40B 'frequent':114C 'h':142C 'h/pr':136C 'hang':9A,51B,112C 'host':22B 'http':6A,43B,93C 'impact':129C 'infrastructur':32B,73C 'n/a':141C 'n/ac':135C 'n/i':140C 'n/s':138C 'n/ui':137C 'network':90C 'oracl':1A,19B,27B,68C 'product':66C 'reachabl':41B 'remot':47B 'repeat':50B,115C 'request':7A 'result':105C 'score':126C 'self':21B 'self-host':20B 'server':12A,31B,72C 'servic':55B,59B 'siebel':2A,24B,28B,63C,69C,96C,120C 'siebel-crm':23B 'success':99C 'support':74C 'u/c':139C 'unauthent':5A,87C 'unauthor':107C 'vector':131C 'vendor':26B 'version':34B,75C 'via':92C 'vulner':60C,85C,103C 'without':44B","nicknames":[],"mitigations":[],"who_affected":"Organizations running Oracle Siebel CRM Deployment in the affected version range 17.0 through 26.9 with HTTP reachable from the network. Sources do not say which deployment configurations are impacted, so the exact scope is unknown.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-20T22:20:45+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","cvss_by":"secalert_us@oracle.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-91421","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-91421","severity":null,"published_at":"2026-10-20T22:20:45+00:00","modified_at":"2026-10-23T21:17:26+00:00","first_seen_at":"2026-10-23T21:57:26+00:00","fetched_at":"2026-10-23T22:29:00+00:00","note":null},{"source":"epss","external_id":"CVE-2026-91421","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-91421","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-25T12:38:52+00:00","fetched_at":"2026-10-25T12:38:52+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}