CVE-2026-83135: Oracle iStore Auth Bypass Vulnerability

CVE-2026-83135 Overview

CVE-2026-83135 is a high-severity vulnerability in the Oracle iStore product of Oracle E-Business Suite, specifically within the Shopping Cart component. Supported versions 12.2.3 through 12.2.15 are affected. A low-privileged attacker with network access over HTTP can exploit the flaw, but successful exploitation requires interaction from a user other than the attacker. The scope changes during exploitation, meaning attacks originating in Oracle iStore can impact additional products. Successful attacks lead to unauthorized creation, deletion, or modification of critical data and complete read access to all iStore-accessible data. The weakness is categorized under CWE-284: Improper Access Control.

Critical Impact
Authenticated attackers can trick another user into triggering requests that compromise the confidentiality and integrity of Oracle iStore data, with cross-product impact due to scope change.

Affected Products

Oracle E-Business Suite — Oracle iStore 12.2.3
Oracle E-Business Suite — Oracle iStore versions 12.2.4 through 12.2.14
Oracle E-Business Suite — Oracle iStore 12.2.15

Discovery Timeline

2026-09-15 - CVE-2026-83135 published to NVD
2026-09-17 - Last updated in NVD database

Technical Details for CVE-2026-83135

Vulnerability Analysis

The vulnerability resides in the Shopping Cart component of Oracle iStore, a customer-facing e-commerce application within Oracle E-Business Suite. An authenticated attacker with low privileges can send crafted HTTP requests that leverage a legitimate user session to perform unauthorized actions. Because the vulnerability produces a scope change, the impact extends beyond Oracle iStore itself and reaches other products deployed alongside it in the E-Business Suite stack. Confidentiality and integrity are both fully compromised, while availability is unaffected. The Exploit Prediction Scoring System (EPSS) currently places this issue in the lower band of near-term exploitation likelihood.

Root Cause

The root cause is improper access control [CWE-284] in the Shopping Cart request-handling logic. The component does not adequately validate whether an authenticated principal is authorized to perform the requested action against a given resource. Combined with user-interaction requirements, this pattern is consistent with vulnerabilities that abuse trust boundaries between browser sessions and server-side authorization checks.

Attack Vector

Exploitation occurs over the network via HTTP against an internet-reachable or intranet-hosted Oracle iStore instance. The attacker must hold a low-privilege iStore account and must induce another user, typically a higher-privileged one, to interact with attacker-supplied content. Once interaction occurs, the crafted request executes in the victim's context and traverses the flawed access control path, resulting in unauthorized reads and modifications across iStore-accessible data and adjacent products.

No verified proof-of-concept code is publicly available. Refer to the Oracle Security Alert September 2026 for authoritative technical details.

Detection Methods for CVE-2026-83135

Indicators of Compromise

Unusual HTTP POST or GET activity targeting Oracle iStore Shopping Cart endpoints originating from low-privileged accounts.
Session activity from authenticated users showing rapid changes to cart, quote, or order objects belonging to other users.
Referer headers pointing to external or unexpected domains preceding sensitive iStore transactions.

Detection Strategies

Inspect Oracle E-Business Suite access logs for cross-user object references and unexpected privilege transitions within iStore modules.
Correlate authentication events with subsequent Shopping Cart write operations to identify patterns consistent with induced user interaction.
Enable Oracle E-Business Suite auditing on iStore tables to record create, update, and delete operations at the row level.

Monitoring Recommendations

Forward Oracle E-Business Suite application and database audit logs to a centralized analytics platform for behavioral baselining.
Alert on iStore accounts performing actions on resources owned by different user IDs within short time windows.
Monitor outbound HTTP traffic from iStore front-ends for links or content originating from untrusted sources that could stage user-interaction attacks.

How to Mitigate CVE-2026-83135

Immediate Actions Required

Apply the fixes documented in the Oracle Security Alert September 2026 to all Oracle iStore deployments running versions 12.2.3 through 12.2.15.
Inventory internet-exposed Oracle iStore endpoints and restrict access where business requirements allow.
Review recent audit logs for suspicious Shopping Cart activity performed by low-privileged accounts.

Patch Information

Oracle addresses this vulnerability in the September 2026 Critical Patch Update cycle. Administrators should follow the patch installation guidance provided in the Oracle Security Alert and validate deployment in a staging environment before pushing to production.

Workarounds

Enforce strict Content Security Policy (CSP) and same-site cookie attributes on the iStore front-end to reduce the effectiveness of induced user-interaction attacks.
Place a web application firewall in front of Oracle iStore with rules that block anomalous Shopping Cart parameters and cross-origin request patterns.
Reduce the privilege of accounts that interact with iStore to the minimum required for their role until patches are applied.

bash

# Example WAF rule concept for blocking cross-origin iStore Shopping Cart writes
# Adjust to the specific WAF syntax in use
SecRule REQUEST_URI "@beginsWith /OA_HTML/ibeCCtpSCtl" \
  "phase:1,deny,status:403,\
   chain,\
   msg:'Blocked cross-origin iStore Shopping Cart request (CVE-2026-83135)'"
  SecRule REQUEST_HEADERS:Origin "!@rx ^https?://(www\.)?example\.com$"