CVE-2026-0603 – Hibernate security issue: Should you be worried?

#softwareengineering #security #java #hibernate

CVE-2026-0603: Second-Order SQL Injection in Hibernate ORM – Risk Assessment

Abstract CVE-2026-0603, disclosed on January 19, 2026, describes a high-severity (CVSS 8.3) second-order SQL injection vulnerability in Hibernate ORM’s InlineIdsOrClauseBuilder. The issue arises when unsanitized string values are incorporated into dynamic IN or OR clauses during query construction. This article examines the vulnerability’s mechanics, affected versions, and conditions under which applications remain unaffected, with particular emphasis on systems that employ sequence-generated numeric primary keys.

Introduction SQL injection vulnerabilities remain a persistent threat in object-relational mapping (ORM) frameworks. CVE-2026-0603 affects Hibernate ORM when string-based identifiers are processed in a manner that permits injection of malicious SQL fragments. The vulnerability is classified as second-order: malicious input must first be stored in the database and later retrieved for use in a dynamic query.

Vulnerability Description The flaw resides in the construction of SQL clauses that combine multiple identifier values. When identifiers are strings, Hibernate may concatenate values without sufficient sanitization, enabling an authenticated attacker with low privileges to store SQL metacharacters (e.g., quotes, comments, semicolons) in a field that later serves as an identifier. Subsequent query execution can result in arbitrary SQL statements, leading to data exposure (high confidentiality impact), unauthorized modification (high integrity impact), or limited denial-of-service (low availability impact).

Affected Versions The vulnerability impacts Hibernate ORM versions 6.0.0 through at least 6.6.41.Final. Earlier 5.x series remain unaffected, as the problematic code path was introduced in the 6.x branch. Red Hat products incorporating vulnerable Hibernate builds (e.g., JBoss EAP, Fuse, OpenShift Application Runtimes) are also exposed. Patches are available through Red Hat errata as of January 19, 2026; an upstream fix in the 6.6.x line is anticipated shortly.

Conditions for Non-Exposure Applications are not vulnerable when primary keys are exclusively numeric (Long/BIGINT) and generated by database sequences. In such cases:

Identifier values are controlled by the database and never originate from user input.
Hibernate processes numeric identifiers as bind parameters or literal numbers, bypassing string concatenation logic.
The vulnerable InlineIdsOrClauseBuilder path is not executed.

This configuration effectively prevents exploitation, even on unpatched versions.

Discussion The use of user-supplied values as primary keys or identifiers introduces unnecessary risk. Numeric, sequence-generated keys provide a robust defense-in-depth layer against injection and enumeration attacks. When user-controlled values (e.g., usernames, slugs, codes) are required, they should be stored in separate indexed columns with strict validation, normalization, and sanitization. Direct use of such values as identifiers violates separation of concerns and increases attack surface.

Conclusion For applications that rely solely on sequence-generated numeric primary keys, CVE-2026-0603 presents no practical risk. Patching remains advisable for general hygiene, but urgency is low in these environments. Systems employing string-based identifiers, particularly those influenced by user input, require prompt remediation.

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