CVE-2026-119277: MariaDB Connector/J: Rogue server can make the client read past the packet through server-declared lengths

Vulnerability summary

CVE-2026-119277 is a medium (CVSS 5.9) Out-of-bounds Read vulnerability in mariadb-corporation mariadb-connector-j. EPSS estimates a 0.35% chance of exploitation in the next 30 days, higher than 28.7% of scored vulnerabilities.

Timeline

1. 29-10-2026
   PublishedVulnerability first disclosed.

Description

MariaDB Connector/J is used to connect applications developed in Java to MariaDB and MySQL databases. From 3.0.0 until 3.3.7, 3.4.5, and 3.5.11, decoders for OK packet session-state blocks, column definition packets, text row data, or binary row data used server-declared lengths without confirming that the requested bytes remained in the receive buffer. The decoders could position reads, create sub-buffers, or decode strings beyond the packet boundary. A malicious or compromised server, or a machine-in-the-middle attacker, could trigger unchecked ArrayIndexOutOfBoundsException or IllegalArgumentException failures inside JDBC calls and terminate connection handling. This issue is fixed in versions 3.3.7, 3.4.5, and 3.5.11.

• CWE-125Out-of-bounds ReadThe product reads data past the end, or before the beginning, of the intended buffer.
• CWE-130Improper Handling of Length Parameter InconsistencyThe product parses a formatted message or structure, but it does not handle or incorrectly handles a length field that is inconsistent with the actual length of the associated data.