---
id: "CVE-2026-119279"
kind: "vulnerability"
aliases: ["CVE-2026-119279"]
title: "MariaDB Connector/J: oversized length value from server crashes or misallocates client"
severity: "medium"
cvss: 5.9
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["java", "jdbc", "mariadb", "mysql", "package"]
not_affected_if: ["trusted-server-only", "version-outside-range"]
published_at: "2026-10-29T21:17:21+00:00"
first_seen_at: "2026-10-29T21:26:52+00:00"
updated_at: "2026-10-29T21:28:46+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-119279", "first_seen_at": "2026-10-29T21:26:52+00:00"}]
---

# MariaDB Connector/J: oversized length value from server crashes or misallocates client

MariaDB Connector/J, the Java driver for MariaDB and MySQL, mishandles unsigned 8-byte length fields from the database server, narrowing them to a Java int without a range check. A malicious or compromised server, or an attacker in the middle of the connection, can cause exceptions, out-of-bounds failures or oversized allocations in the client.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the Connector/J version in the project's build file (for example `pom.xml` or `build.gradle`) or the `mariadb-java-client` jar on the classpath.
- Confirm whether the app connects to a server that is not fully trusted or over a network path an attacker could intercept.

## Fix

- Move to `3.3.7`, `3.4.5`, or `3.5.10` depending on the release line in use.

## Timeline

- 2026-10-29T21:26:52+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-119279

## From the sources

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 3.5.10, the ReadableByteBuf.readLength() and ReadableByteBuf.readIntLengthEncodedNotNull() methods narrowed the protocol's unsigned 8-byte length-encoded integer to a Java int without checking that the value fit a non-negative integer. Values above Integer.MAX_VALUE could wrap to a negative or unrelated length that downstream allocation and read paths used. A malicious or compromised server, or a machine-in-the-middle attacker, could trigger NegativeArraySizeException, out-of-bounds failures, or oversized allocation behavior in client connection handling. This issue is fixed in versions 3.3.7, 3.4.5, and 3.5.10.

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