{"id":"CVE-2026-91657","kind":"vulnerability","aliases":["CVE-2026-91657"],"related":[],"title":"Oracle Essbase: low-privilege HTTP user can read a subset of data","description":"Vulnerability in Oracle Essbase (component: Security).   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.  Successful attacks of this vulnerability can result in  unauthorized read access to a subset of Oracle Essbase accessible data. CVSS 3.1 Base Score 4.3 (Confidentiality impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N).","summary":"A flaw in the Security component of Oracle Essbase 21.8.3.0.0 lets an attacker with a low-privilege account reach the product over HTTP. A successful attack gives unauthorized read access to a subset of data Essbase holds.","severity":"medium","cvss":4.3,"epss":0.00184,"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":[],"how_to_check":"- Confirm the installed Essbase version is `21.8.3.0.0` (unknown how to read it from the sources; check the Essbase admin console or installed package)","fix":"- Apply the Oracle Critical Patch Update that addresses CVE-2026-91657 for Essbase (unknown fixed version in 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":"2026-10-25T04:37:47+00:00","updated_at":"2026-10-25T04:37:47+00:00","category":"vendor","confidence":0.6,"triage":{"at":"2026-10-25T04:37:47Z","model":"claude-haiku-5-5","output":{"fix":"- Apply the Oracle Critical Patch Update that addresses CVE-2026-91657 for Essbase (unknown fixed version in the sources)","reach":"network","title":"Oracle Essbase: low-privilege HTTP user can read a subset of data","impact":"low","summary":"A flaw in the Security component of Oracle Essbase 21.8.3.0.0 lets an attacker with a low-privilege account reach the product over HTTP. A successful attack gives unauthorized read access to a subset of data Essbase holds.","category":"vendor","nicknames":[],"who_cares":["oracle-essbase","self-hosted"],"confidence":0.6,"needs_auth":"yes","worst_case":"unauthorized read access to a subset of Essbase data","analyst_note":"Find the fixed version and the Oracle CPU advisory for CVE-2026-91657 at https://nvd.nist.gov/vuln/detail/CVE-2026-91657; the sources give only the affected version.","how_to_check":"- Confirm the installed Essbase version is `21.8.3.0.0` (unknown how to read it from the sources; check the Essbase admin console or installed package)","needs_analyst":true,"not_affected_if":[],"who_is_affected":"Organizations running Oracle Essbase 21.8.3.0.0 that expose its HTTP interface to users with some account on the server. The sources do not describe a non-default configuration requirement.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.000612,"input_tokens":3480,"output_tokens":528,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-2026':15A,18A '-91657':16A,19A '/av':127C '21.8.3.0.0':38B,80C '3.1':117C,126C '4.3':120C 'access':59B,90C,107C,114C 'account':47B 'affect':78C 'allow':84C 'attack':41B,55B,87C,98C 'base':118C 'compon':34B,71C 'compromis':94C 'confidenti':121C 'cve':14A,17A 'cvss':116C,123C,125C 'data':13A,64B,115C 'easili':81C 'essbas':2A,24B,37B,65B,70C,96C,113C 'essbase':21A 'exploit':82C 'flaw':30B 'give':56B 'hold':66B 'host':27B 'http':6A,52B,92C 'impact':122C 'l/i':133C 'l/pr':129C 'l/ui':130C 'let':39B 'low':4A,45B,85C 'low-privileg':3A,44B 'n':135C 'n/a':134C 'n/ac':128C 'n/s':131C 'network':89C 'oracl':1A,23B,36B,69C,95C,112C 'oracle':20A 'oracle-essbas':22B 'privileg':5A,46B,86C 'product':50B 'reach':48B 'read':9A,58B,106C 'result':103C 'score':119C 'secur':33B,72C 'self':26B 'self-host':25B 'subset':11A,62B,110C 'success':54B,97C 'support':74C 'u/c':132C 'unauthor':57B,105C 'user':7A 'vector':124C 'vendor':28B 'version':75C 'via':91C 'vulner':67C,83C,101C","nicknames":[],"mitigations":[],"who_affected":"Organizations running Oracle Essbase 21.8.3.0.0 that expose its HTTP interface to users with some account on the server. The sources do not describe a non-default configuration requirement.","tier":"C","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:U/C:L/I:N/A:N","cvss_by":"secalert_us@oracle.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-91657","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-91657","severity":null,"published_at":"2026-10-20T22:21:06+00:00","modified_at":"2026-10-23T17:19:08+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-2026-91657","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-91657","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"}