CVE-2026-33815: Jackc pgx memory-safety vulnerability in pgproto3

Executive brief

pgx is a widely used software library that allows Go applications to communicate with PostgreSQL databases. A critical security flaw has been identified that could allow an attacker to interfere with the application's memory. This could lead to unauthorized access to sensitive data, system crashes, or the ability for an attacker to take control of the application.

Technical details

A memory-safety vulnerability exists in the pgx toolkit (github.com/jackc/pgx/v5) prior to version 5.9.0. The flaw allows for potential memory corruption or unauthorized memory access via the network without requiring authentication or user interaction. While specific CWE details are not provided in the advisory, the CVSS score of 9.8 and the 'memory-safety' classification suggest a high risk of remote code execution (RCE) or information disclosure. The issue is addressed in version 5.9.0.

Affected products

• jackc pgx < 5.9.0

Timeline

• 2026-04-07: disclosed
• 2026-04-07: advisory
• 2026-04-10: other: GitHub reviewed

References

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