CVE-2026-83491: Oracle iRecruitment Auth Bypass Vulnerability

CVE-2026-83491 Overview

CVE-2026-83491 is a vulnerability in the Oracle iRecruitment product of Oracle E-Business Suite, within the Internal Operations component. Affected versions span 12.2.3 through 12.2.15. An unauthenticated attacker with access to the physical communication segment attached to the hardware running Oracle iRecruitment can compromise the application. Successful exploitation results in unauthorized creation, deletion, or modification of critical data, along with unauthorized read access to all Oracle iRecruitment accessible data.

Critical Impact
Adjacent-network attackers can achieve unauthorized read and write access to all data accessible by Oracle iRecruitment, affecting both confidentiality and integrity of recruitment records.

Affected Products

Oracle E-Business Suite - Oracle iRecruitment 12.2.3
Oracle E-Business Suite - Oracle iRecruitment versions 12.2.4 through 12.2.14
Oracle E-Business Suite - Oracle iRecruitment 12.2.15

Discovery Timeline

2026-09-15 - CVE CVE-2026-83491 published to NVD
2026-09-16 - Last updated in NVD database

Technical Details for CVE-2026-83491

Vulnerability Analysis

The vulnerability resides in the Internal Operations component of Oracle iRecruitment, part of the Oracle E-Business Suite. Exploitation requires network adjacency, meaning the attacker must be positioned on the same physical communication segment as the target host. No authentication and no user interaction are required.

A successful attack yields unauthorized read access to all data reachable by the iRecruitment application, together with unauthorized creation, deletion, or modification of that data. Availability of the service is not affected. Because iRecruitment handles applicant and employee records, an intrusion exposes personally identifiable information (PII) and hiring workflow data.

Oracle classifies exploitation as difficult. The adjacency requirement narrows the exploitation surface primarily to attackers with a foothold inside the internal network, connected VPN segments, or a compromised device on the same broadcast domain as the application server.

Root Cause

Oracle has not published the precise technical root cause in the public advisory. The vulnerability affects the Internal Operations component of iRecruitment and is exploitable without credentials from an adjacent network position. Refer to the Oracle Security Alert September 2026 for vendor-supplied details.

Attack Vector

The attack vector is adjacent network. An attacker must reach the physical or logical network segment attached to the host running Oracle iRecruitment. From that position, the attacker interacts with the iRecruitment service without authenticating and without any user interaction. The exploitation flow bypasses application authentication controls to read and write iRecruitment-accessible data.

No public proof-of-concept exploit is available. No exploitation activity has been reported, and the issue is not listed in the CISA Known Exploited Vulnerabilities catalog.

Detection Methods for CVE-2026-83491

Indicators of Compromise

Unexpected create, update, or delete operations against iRecruitment tables or candidate records outside normal HR workflows.
Unauthenticated or anomalous session activity originating from hosts on the internal segment adjacent to the E-Business Suite application tier.
Access patterns to Internal Operations endpoints from workstations that do not normally interact with the iRecruitment application.

Detection Strategies

Enable and review Oracle E-Business Suite audit trails for the iRecruitment schema, focusing on PER_ALL_PEOPLE_F, IRC_*, and related tables.
Correlate application-tier access logs with network flow data to identify sessions originating from unexpected adjacent hosts.
Baseline normal HR-user activity and alert on write operations performed outside business hours or from non-HR subnets.

Monitoring Recommendations

Forward Oracle E-Business Suite application, database, and access logs to a centralized analytics platform for correlation.
Monitor east-west traffic on the segment hosting the E-Business Suite application tier for unauthenticated protocol interactions.
Alert on privilege changes, bulk record modifications, and schema-level operations that fall outside change-management windows.

How to Mitigate CVE-2026-83491

Immediate Actions Required

Apply the Oracle Critical Patch Update associated with the Oracle Security Alert September 2026 to all affected iRecruitment deployments.
Inventory all Oracle E-Business Suite installations and confirm which run iRecruitment 12.2.3 through 12.2.15.
Restrict adjacent-network access to the E-Business Suite application tier through VLAN segmentation and access control lists.

Patch Information

Oracle addressed CVE-2026-83491 in the September 2026 Critical Patch Update. Administrators should download and apply the patches referenced in the Oracle Security Alert September 2026 using the standard Oracle E-Business Suite patching procedure. Validate the patch in a non-production environment before production rollout.

Workarounds

Isolate the E-Business Suite application tier on a dedicated network segment with strict ingress and egress controls.
Enforce network access control (802.1X) on switches serving the application-tier segment to prevent unauthorized adjacent devices.
Disable or restrict the iRecruitment module in environments where it is not actively used until the patch is applied.

bash

# Example: restrict adjacent access to the E-Business Suite application tier
# Replace interface and subnet values with those of your environment
iptables -A INPUT -s 10.10.20.0/24 -p tcp --dport 8000 -j ACCEPT
iptables -A INPUT -p tcp --dport 8000 -j DROP