The SentinelOne Annual Threat Report - A Defenders Guide from the FrontlinesThe SentinelOne Annual Threat ReportGet the Report
Experiencing a Breach?Blog
Get StartedContact Us
SentinelOne
  • Platform
    Platform Overview
    • Singularity Platform
      Welcome to Integrated Enterprise Security
    • AI for Security
      Leading the Way in AI-Powered Security Solutions
    • Securing AI
      Accelerate AI Adoption with Secure AI Tools, Apps, and Agents.
    • How It Works
      The Singularity XDR Difference
    • Singularity Marketplace
      One-Click Integrations to Unlock the Power of XDR
    • Pricing & Packaging
      Comparisons and Guidance at a Glance
    Data & AI
    • Purple AI
      Accelerate SecOps with Generative AI
    • Singularity Hyperautomation
      Easily Automate Security Processes
    • AI-SIEM
      The AI SIEM for the Autonomous SOC
    • Singularity Data Lake
      AI-Powered, Unified Data Lake
    • Singularity Data Lake for Log Analytics
      Seamlessly Ingest Data from On-Prem, Cloud or Hybrid Environments
    Endpoint Security
    • Singularity Endpoint
      Autonomous Prevention, Detection, and Response
    • Singularity XDR
      Native & Open Protection, Detection, and Response
    • Singularity RemoteOps Forensics
      Orchestrate Forensics at Scale
    • Singularity Threat Intelligence
      Comprehensive Adversary Intelligence
    • Singularity Vulnerability Management
      Application & OS Vulnerability Management
    • Singularity Identity
      Identity Threat Detection and Response
    Cloud Security
    • Singularity Cloud Security
      Block Attacks with an AI-Powered CNAPP
    • Singularity Cloud Native Security
      Secure Cloud and Development Resources
    • Singularity Cloud Workload Security
      Real-Time Cloud Workload Protection Platform
    • Singularity Cloud Data Security
      AI-Powered Threat Detection for Cloud Storage
    • Singularity Cloud Security Posture Management
      Detect and Remediate Cloud Misconfigurations
    Securing AI
    • Prompt Security
      Secure AI Tools Across Your Enterprise
  • Why SentinelOne?
    Why SentinelOne?
    • Why SentinelOne?
      Cybersecurity Built for What’s Next
    • Our Customers
      Trusted by the World’s Leading Enterprises
    • Industry Recognition
      Tested and Proven by the Experts
    • About Us
      The Industry Leader in Autonomous Cybersecurity
    Compare SentinelOne
    • Arctic Wolf
    • Broadcom
    • CrowdStrike
    • Cybereason
    • Microsoft
    • Palo Alto Networks
    • Sophos
    • Splunk
    • Trellix
    • Trend Micro
    • Wiz
    Verticals
    • Energy
    • Federal Government
    • Finance
    • Healthcare
    • Higher Education
    • K-12 Education
    • Manufacturing
    • Retail
    • State and Local Government
  • Services
    Managed Services
    • Managed Services Overview
      Wayfinder Threat Detection & Response
    • Threat Hunting
      World-Class Expertise and Threat Intelligence
    • Managed Detection & Response
      24/7/365 Expert MDR Across Your Entire Environment
    • Incident Readiness & Response
      DFIR, Breach Readiness, & Compromise Assessments
    Support, Deployment, & Health
    • Technical Account Management
      Customer Success with Personalized Service
    • SentinelOne GO
      Guided Onboarding & Deployment Advisory
    • SentinelOne University
      Live and On-Demand Training
    • Services Overview
      Comprehensive Solutions for Seamless Security Operations
    • SentinelOne Community
      Community Login
  • Partners
    Our Network
    • MSSP Partners
      Succeed Faster with SentinelOne
    • Singularity Marketplace
      Extend the Power of S1 Technology
    • Cyber Risk Partners
      Enlist Pro Response and Advisory Teams
    • Technology Alliances
      Integrated, Enterprise-Scale Solutions
    • SentinelOne for AWS
      Hosted in AWS Regions Around the World
    • Channel Partners
      Deliver the Right Solutions, Together
    • SentinelOne for Google Cloud
      Unified, Autonomous Security Giving Defenders the Advantage at Global Scale
    • Partner Locator
      Your Go-to Source for Our Top Partners in Your Region
    Partner Portal→
  • Resources
    Resource Center
    • Case Studies
    • Data Sheets
    • eBooks
    • Reports
    • Videos
    • Webinars
    • Whitepapers
    • Events
    View All Resources→
    Blog
    • Feature Spotlight
    • For CISO/CIO
    • From the Front Lines
    • Identity
    • Cloud
    • macOS
    • SentinelOne Blog
    Blog→
    Tech Resources
    • SentinelLABS
    • Ransomware Anthology
    • Cybersecurity 101
  • About
    About SentinelOne
    • About SentinelOne
      The Industry Leader in Cybersecurity
    • Investor Relations
      Financial Information & Events
    • SentinelLABS
      Threat Research for the Modern Threat Hunter
    • Careers
      The Latest Job Opportunities
    • Press & News
      Company Announcements
    • Cybersecurity Blog
      The Latest Cybersecurity Threats, News, & More
    • FAQ
      Get Answers to Our Most Frequently Asked Questions
    • DataSet
      The Live Data Platform
    • S Foundation
      Securing a Safer Future for All
    • S Ventures
      Investing in the Next Generation of Security, Data and AI
  • Pricing
Get StartedContact Us
CVE Vulnerability Database
Vulnerability Database/CVE-2023-21893

CVE-2023-21893: Oracle Database Server Auth Bypass Flaw

CVE-2023-21893 is an authentication bypass vulnerability in Oracle Data Provider for .NET component of Oracle Database Server affecting versions 19c and 21c. This article covers technical details, affected versions, and mitigation.

Published: February 11, 2026

CVE-2023-21893 Overview

CVE-2023-21893 is an Improper Access Control vulnerability affecting the Oracle Data Provider for .NET component of Oracle Database Server. This vulnerability allows an unauthenticated attacker with network access via TCPS to potentially compromise the Oracle Data Provider for .NET component. Successful exploitation requires human interaction and can result in a complete takeover of the affected component, impacting confidentiality, integrity, and availability.

Critical Impact

Successful exploitation can result in complete takeover of Oracle Data Provider for .NET, affecting confidentiality, integrity, and availability of database operations.

Affected Products

  • Oracle Database Server 19c
  • Oracle Database Server 21c
  • Database client-only installations on Windows platform

Discovery Timeline

  • 2023-01-18 - CVE CVE-2023-21893 published to NVD
  • 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2023-21893

Vulnerability Analysis

This vulnerability resides in the Oracle Data Provider for .NET component, which serves as the data access layer for .NET applications connecting to Oracle databases. The security weakness is classified as CWE-284 (Improper Access Control), indicating that the component fails to properly restrict access or permissions to resources.

The exploitation complexity is considered high due to specific conditions that must be met for a successful attack. The vulnerability requires the attacker to induce a user to perform an action (such as clicking a malicious link or connecting to a rogue server) while the attacker maintains network access via TCPS (TCP with SSL/TLS). Despite these requirements, successful exploitation grants the attacker significant control over the affected component.

Root Cause

The vulnerability stems from improper access control mechanisms within the Oracle Data Provider for .NET component. The component fails to adequately validate or restrict certain operations when handling TCPS connections, allowing unauthorized actions to be performed under specific conditions. This affects both full Oracle Database Server installations and standalone database client installations on Windows platforms.

Attack Vector

The attack leverages network access through TCPS (secure TCP connections). An attacker must:

  1. Position themselves with network access to the target system
  2. Establish or intercept TCPS communications
  3. Induce user interaction to trigger the vulnerable code path
  4. Exploit the improper access control to gain unauthorized access

The network-based attack vector combined with the requirement for user interaction makes this a targeted attack scenario, typically requiring social engineering or man-in-the-middle positioning. The use of TCPS suggests the vulnerability may involve certificate validation bypass or trust relationship exploitation within the secure connection handling.

Detection Methods for CVE-2023-21893

Indicators of Compromise

  • Unusual TCPS connection patterns to Oracle Database servers from untrusted sources
  • Unexpected authentication events or access attempts within Oracle Data Provider logs
  • Anomalous .NET application behavior when connecting to Oracle databases
  • Network traffic anomalies on Oracle database ports involving TCPS connections

Detection Strategies

  • Monitor network traffic for suspicious TCPS connections targeting Oracle Database ports
  • Implement application-level logging for Oracle Data Provider for .NET operations
  • Deploy network intrusion detection rules to identify potential exploitation attempts
  • Review Windows event logs for unusual .NET application behavior on database clients

Monitoring Recommendations

  • Enable detailed logging for Oracle Data Provider for .NET connections
  • Configure alerts for authentication failures or unusual access patterns
  • Monitor for unexpected certificate operations or trust relationship changes
  • Implement endpoint detection and response (EDR) solutions to track database client activity

How to Mitigate CVE-2023-21893

Immediate Actions Required

  • Apply the Oracle January 2023 Critical Patch Update immediately
  • Review and restrict network access to Oracle Database servers
  • Audit all systems running Oracle Database Server 19c or 21c
  • Verify all Windows database client installations are updated

Patch Information

Oracle has addressed this vulnerability in the January 2023 Critical Patch Update. Organizations should obtain and apply the appropriate patches from the Oracle January 2023 Security Alert. The patch addresses the improper access control issue in the Oracle Data Provider for .NET component for both database server and client-only installations.

Workarounds

  • Restrict TCPS network access to Oracle Database servers using firewall rules
  • Implement network segmentation to limit exposure of database infrastructure
  • Configure strict certificate validation policies for TCPS connections
  • Monitor and limit user access to database client applications where possible
  • Consider temporarily disabling unnecessary TCPS connections until patches can be applied

Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.

  • Vulnerability Details
  • TypeAuth Bypass
  • Vendor/TechOracle Database
  • SeverityHIGH
  • CVSS Score7.5
  • EPSS Probability1.06%
  • Known ExploitedNo
  • CVSS Vector
  • CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
  • Impact Assessment
  • ConfidentialityHigh
  • IntegrityHigh
  • AvailabilityHigh
  • CWE References
  • NVD-CWE-noinfo
  • CWE-284
  • Vendor Resources
  • Oracle January 2023 Security Alert
  • Related CVEs
  • CVE-2026-21939: Oracle SQLcl Auth Bypass Vulnerability
  • CVE-2023-21949: Oracle Database Server Auth Bypass Flaw
  • CVE-2021-2335: Oracle Database Auth Bypass Vulnerability
  • CVE-2021-2334: Oracle Database Auth Bypass Vulnerability
Experience the World’s Most Advanced Cybersecurity Platform

Experience the World’s Most Advanced Cybersecurity Platform

See how our intelligent, autonomous cybersecurity platform can protect your organization now and into the future.

Try SentinelOne
  • Get Started
  • Get a Demo
  • Product Tour
  • Why SentinelOne
  • Pricing & Packaging
  • FAQ
  • Contact
  • Contact Us
  • Customer Support
  • SentinelOne Status
  • Language
  • Platform
  • Singularity Platform
  • Singularity Endpoint
  • Singularity Cloud
  • Singularity AI-SIEM
  • Singularity Identity
  • Singularity Marketplace
  • Purple AI
  • Services
  • Wayfinder TDR
  • SentinelOne GO
  • Technical Account Management
  • Support Services
  • Verticals
  • Energy
  • Federal Government
  • Finance
  • Healthcare
  • Higher Education
  • K-12 Education
  • Manufacturing
  • Retail
  • State and Local Government
  • Cybersecurity for SMB
  • Resources
  • Blog
  • Labs
  • Case Studies
  • Videos
  • Product Tours
  • Events
  • Cybersecurity 101
  • eBooks
  • Webinars
  • Whitepapers
  • Press
  • News
  • Ransomware Anthology
  • Company
  • About Us
  • Our Customers
  • Careers
  • Partners
  • Legal & Compliance
  • Security & Compliance
  • Investor Relations
  • S Foundation
  • S Ventures

©2026 SentinelOne, All Rights Reserved.

Privacy Notice Terms of Use

English