CVE-2024-21233: Oracle Database Server Auth Bypass Flaw

CVE-2024-21233 Overview

CVE-2024-21233 is a vulnerability in the Oracle Database Core component of Oracle Database Server that allows authenticated attackers with low privileges to compromise data integrity. The flaw affects multiple supported versions of Oracle Database Server and can be exploited remotely via Oracle Net protocol by attackers with only the Create Session privilege.

This vulnerability enables unauthorized modification operations including update, insert, or delete access to data managed by the Oracle Database Core component. The ease of exploitation combined with the network-based attack vector makes this a significant concern for organizations running affected Oracle Database deployments.

Critical Impact

Low-privileged attackers can perform unauthorized data modifications to Oracle Database Core accessible data through network-based exploitation via Oracle Net.

Affected Products

• Oracle Database Server versions 19.3 through 19.24
• Oracle Database Server versions 21.3 through 21.15
• Oracle Database Server versions 23.4 and 23.5

Discovery Timeline

• 2024-10-15 - CVE-2024-21233 published to NVD
• 2024-10-31 - Last updated in NVD database

Technical Details for CVE-2024-21233

Vulnerability Analysis

The vulnerability resides in the Oracle Database Core component, which handles fundamental database operations. An authenticated attacker with minimal privileges (specifically the Create Session privilege) can exploit this flaw to perform unauthorized data manipulation operations on Oracle Database Core accessible data.

The attack is conducted remotely through the Oracle Net protocol, Oracle's networking layer that handles communication between client applications and Oracle Database servers. The vulnerability is classified under CWE-203 (Observable Discrepancy), suggesting potential information exposure through timing or behavioral differences that could facilitate the attack.

The flaw requires no user interaction and presents low attack complexity, making it straightforward to exploit once an attacker has established a valid session. While the vulnerability does not impact confidentiality or availability, the integrity impact allows attackers to modify, insert, or delete data they should not have access to.

Root Cause

The root cause relates to improper access control validation within the Oracle Database Core component. When processing certain operations via Oracle Net, the component fails to adequately verify that the authenticated user has appropriate authorization for the requested data modification operations. This allows users with basic session privileges to perform data manipulation beyond their intended authorization scope.

Attack Vector

The attack leverages network access via Oracle Net protocol to target the vulnerable Oracle Database Core component. An attacker requires:

1. Network connectivity to the Oracle Database Server (typically port 1521)
2. Valid credentials with at minimum Create Session privilege
3. Knowledge of accessible data structures within the Oracle Database Core

Once connected, the attacker can craft malicious requests that bypass normal authorization checks, enabling unauthorized update, insert, or delete operations on data accessible through the Oracle Database Core component. The vulnerability does not require elevated privileges or user interaction, making exploitation relatively straightforward for authenticated adversaries.

Detection Methods for CVE-2024-21233

Indicators of Compromise

• Unexpected data modifications in Oracle Database Core managed tables without corresponding legitimate user activity
• Audit log entries showing data manipulation operations from sessions with only Create Session privileges
• Anomalous Oracle Net traffic patterns from low-privileged user accounts

Detection Strategies

• Enable Oracle Database Unified Auditing to capture all DML operations and correlate with user privileges
• Monitor for sessions with Create Session privilege performing unexpected UPDATE, INSERT, or DELETE operations
• Implement database activity monitoring to detect unauthorized data modification attempts
• Review Oracle listener logs for suspicious connection patterns

Monitoring Recommendations

• Configure real-time alerting for data modifications by users with minimal privileges
• Establish baseline behavior for Oracle Net traffic and alert on deviations
• Regularly audit user privileges and remove unnecessary Create Session grants
• Monitor Oracle alert logs for security-related warnings

How to Mitigate CVE-2024-21233

Immediate Actions Required

• Apply the Oracle Critical Patch Update (CPU) from October 2024 immediately
• Review and restrict Create Session privileges to only essential users
• Implement network segmentation to limit Oracle Net access to trusted clients
• Enable comprehensive database auditing to detect exploitation attempts

Patch Information

Oracle has released security patches addressing this vulnerability in the October 2024 Critical Patch Update (CPU). Organizations should apply the appropriate patch for their Oracle Database Server version (19.x, 21.x, or 23.x). The patch is available through Oracle Security Advisory October 2024.

SentinelOne customers benefit from automated detection of suspicious database activities and network anomalies that may indicate exploitation attempts. The Singularity platform provides visibility into Oracle Database server endpoints and can detect post-exploitation behaviors.

Workarounds

• Restrict network access to Oracle Database servers using firewall rules and network ACLs
• Implement Oracle Database Vault to add additional access control layers
• Revoke Create Session privilege from unnecessary user accounts pending patch deployment
• Enable Oracle Label Security for enhanced data access controls on sensitive information