CVE-2026-39349 Overview
OrangeHRM, a comprehensive human resource management (HRM) system, contains a cryptographic vulnerability in versions 5.0 through 5.8. The application encrypts certain sensitive fields using AES in Electronic Codebook (ECB) mode, which is a fundamentally weak encryption approach. ECB mode preserves block-aligned plaintext patterns in the ciphertext, enabling pattern disclosure attacks against stored data. This weakness in the encryption implementation can allow attackers to infer information about encrypted sensitive HR data.
Critical Impact
Sensitive HR data encrypted with AES-ECB may reveal plaintext patterns, potentially exposing employee information through cryptographic pattern analysis.
Affected Products
- OrangeHRM Open Source versions 5.0 through 5.8
Discovery Timeline
- 2026-04-07 - CVE-2026-39349 published to NVD
- 2026-04-08 - Last updated in NVD database
Technical Details for CVE-2026-39349
Vulnerability Analysis
This vulnerability stems from the improper use of AES encryption in Electronic Codebook (ECB) mode for protecting sensitive fields within the OrangeHRM application. ECB mode is the simplest block cipher mode of operation, where each block of plaintext is encrypted independently using the same key. While this approach is computationally efficient, it presents a significant cryptographic weakness: identical plaintext blocks produce identical ciphertext blocks.
In a human resource management system context, this is particularly concerning because HR data often contains repetitive patterns—such as standardized job titles, department names, salary ranges, or status codes. An attacker with access to the encrypted database could perform pattern analysis to identify these repeating structures without needing to decrypt the data directly. This type of vulnerability is classified under CWE-326 (Inadequate Encryption Strength).
Root Cause
The root cause of this vulnerability is the selection of ECB mode for AES encryption instead of more secure modes such as CBC (Cipher Block Chaining), GCM (Galois/Counter Mode), or CTR (Counter Mode). These alternative modes introduce mechanisms like initialization vectors (IVs) or authentication tags that ensure identical plaintext blocks produce different ciphertext blocks, eliminating the pattern preservation weakness inherent to ECB mode.
Attack Vector
The attack vector is network-based but requires specific conditions for exploitation. An attacker would need access to the encrypted data stored in the OrangeHRM database—either through direct database access, a database breach, or by intercepting stored encrypted values. Once the encrypted data is obtained, the attacker can perform block-level pattern analysis to identify repeating data structures.
For example, if multiple employees share the same encrypted job title or department code, these would appear as identical ciphertext blocks. By analyzing the frequency and distribution of these patterns across the dataset, an attacker could potentially infer the underlying plaintext values, especially when combined with known plaintext attack techniques or by correlating patterns with publicly available information.
The vulnerability requires high privileges and specific attack conditions to exploit, which contributes to its low severity classification. However, organizations handling sensitive employee data should still address this cryptographic weakness to maintain defense-in-depth security posture.
Detection Methods for CVE-2026-39349
Indicators of Compromise
- Unusual database access patterns targeting fields containing encrypted sensitive data
- Evidence of bulk data extraction from OrangeHRM database tables
- Unauthorized queries or exports of encrypted field values from the HR system
Detection Strategies
- Monitor database access logs for abnormal read operations on tables containing encrypted sensitive fields
- Implement database activity monitoring (DAM) to detect bulk data extraction attempts
- Review application logs for unusual API calls that return encrypted field data
Monitoring Recommendations
- Enable comprehensive database auditing for all SELECT operations on sensitive HR data tables
- Configure alerts for large-scale data exports or unusual query patterns against the OrangeHRM database
- Implement file integrity monitoring on database backup files to detect unauthorized access
How to Mitigate CVE-2026-39349
Immediate Actions Required
- Upgrade OrangeHRM Open Source to version 5.8.1 or later, which contains the fix for this vulnerability
- Review and audit access controls to the OrangeHRM database to limit exposure of encrypted data
- Assess whether any encrypted data may have been exposed and consider re-encrypting sensitive fields after upgrading
Patch Information
OrangeHRM has addressed this vulnerability in version 5.8.1. The fix replaces the insecure AES-ECB encryption implementation with a more secure encryption mode that does not preserve plaintext patterns. Organizations should update to this version as soon as possible to ensure sensitive HR data is properly protected.
For more information, see the GitHub Security Advisory.
Workarounds
- Implement additional access controls to restrict database-level access to encrypted sensitive fields
- Consider deploying transparent data encryption (TDE) at the database level as an additional layer of protection
- Apply network segmentation to isolate the OrangeHRM database from untrusted network zones
- If immediate patching is not possible, evaluate implementing application-level encryption with secure modes (CBC, GCM) as an interim measure
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
