{"id":"CVE-2026-91659","kind":"vulnerability","aliases":["CVE-2026-91659"],"related":[],"title":"Oracle Essbase Build component flaw exposes critical data over HTTP","description":"Vulnerability in Oracle Essbase (component: Build).   The supported version that is affected is 21.8.3.0.0. Easily exploitable vulnerability allows low privileged attacker with network access via HTTP to compromise Oracle Essbase.  While the vulnerability is in Oracle Essbase, attacks may significantly impact additional products (scope change).  Successful attacks of this vulnerability can result in  unauthorized access to critical data or complete access to all Oracle Essbase accessible data. CVSS 3.1 Base Score 7.7 (Confidentiality impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N).","summary":"A flaw in the Build component of Oracle Essbase 21.8.3.0.0 lets a low-privileged user reach data over HTTP. The sources say a successful attack gives unauthorized access to critical data and all Essbase-accessible data, with scope change to other products.","severity":"high","cvss":7.7,"epss":0.00228,"exploited":false,"exploited_at":null,"products":[{"name":"oracle essbase","fixed":[],"affected":"= 21.8.3.0.0","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["oracle-essbase","self-hosted","vendor"],"not_affected_if":["auth-required"],"how_to_check":"- Confirm the installed Essbase version against `21.8.3.0.0`\n- unknown","fix":"- Apply the Oracle Critical Patch Update fix for Essbase; the fixed version is unknown from the sources","status":"open","published_at":"2026-10-20T22:21:06+00:00","first_seen_at":"2026-10-23T21:57:27+00:00","triaged_at":"2026-10-25T03:10:33+00:00","updated_at":"2026-10-25T03:10:33+00:00","category":"vendor","confidence":0.6,"triage":{"at":"2026-10-25T03:10:33Z","model":"claude-haiku-5-5","output":{"fix":"- Apply the Oracle Critical Patch Update fix for Essbase; the fixed version is unknown from the sources","reach":"internet","title":"Oracle Essbase Build component flaw exposes critical data over HTTP","impact":"high","summary":"A flaw in the Build component of Oracle Essbase 21.8.3.0.0 lets a low-privileged user reach data over HTTP. The sources say a successful attack gives unauthorized access to critical data and all Essbase-accessible data, with scope change to other products.","category":"vendor","nicknames":[],"who_cares":["oracle-essbase","self-hosted"],"confidence":0.6,"needs_auth":"yes","worst_case":"Attacker reads critical Essbase data and data from connected products","analyst_note":"Check the Oracle Critical Patch Update advisory for the fixed Essbase version and whether the HTTP interface is internet-facing; the NVD page (https://nvd.nist.gov/vuln/detail/CVE-2026-91659) may give more detail.","how_to_check":"- Confirm the installed Essbase version against `21.8.3.0.0`\n- unknown","needs_analyst":true,"not_affected_if":["auth-required"],"who_is_affected":"Organizations running Oracle Essbase 21.8.3.0.0 with HTTP access reachable by low-privileged users. Systems on other Essbase versions or without network exposure are not described as affected by the sources.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000619,"input_tokens":3519,"output_tokens":534,"severity_before":"high"},"analyst_status":null,"analyst_note":null,"search":"'-2026':12A,15A '-91659':13A,16A '/av':148C '21.8.3.0.0':35B,83C '3.1':138C,147C '7.7':141C 'access':54B,62B,93C,124C,130C,135C 'addit':111C 'affect':81C 'allow':87C 'attack':51B,90C,107C,116C 'base':139C 'build':3A,30B,75C 'c/c':153C 'chang':66B,114C 'complet':129C 'compon':4A,31B,74C 'compromis':97C 'confidenti':142C 'critic':7A,56B,126C 'cve':11A,14A 'cvss':137C,144C,146C 'data':8A,43B,57B,63B,127C,136C 'easili':84C 'essbas':2A,21B,34B,61B,73C,99C,106C,134C 'essbase':18A 'essbase-access':60B 'exploit':85C 'expos':6A 'flaw':5A,27B 'give':52B 'h/i':154C 'host':24B 'http':10A,45B,95C 'impact':110C,143C 'l/pr':150C 'l/ui':151C 'let':36B 'low':39B,88C 'low-privileg':38B 'may':108C 'n':156C 'n/a':155C 'n/ac':149C 'n/s':152C 'network':92C 'oracl':1A,20B,33B,72C,98C,105C,133C 'oracle':17A 'oracle-essbas':19B 'privileg':40B,89C 'product':69B,112C 'reach':42B 'result':121C 'say':48B 'scope':65B,113C 'score':140C 'self':23B 'self-host':22B 'signific':109C 'sourc':47B 'success':50B,115C 'support':77C 'unauthor':53B,123C 'user':41B 'vector':145C 'vendor':25B 'version':78C 'via':94C 'vulner':70C,86C,102C,119C","nicknames":[],"mitigations":[],"who_affected":"Organizations running Oracle Essbase 21.8.3.0.0 with HTTP access reachable by low-privileged users. Systems on other Essbase versions or without network exposure are not described as affected by the sources.","tier":"B","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-20T22:21:06+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","cvss_by":"secalert_us@oracle.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-91659","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-91659","severity":null,"published_at":"2026-10-20T22:21:06+00:00","modified_at":"2026-10-23T17:18:53+00:00","first_seen_at":"2026-10-23T21:57:27+00:00","fetched_at":"2026-10-23T22:29:01+00:00","note":null},{"source":"epss","external_id":"CVE-2026-91659","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-91659","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-24T13:15:55+00:00","fetched_at":"2026-10-24T13:15:55+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"}