CVE-2026-119279: MariaDB Connector/J: Length-encoded integers larger than Integer.MAX_VALUE were truncated before being used as lengths

Severity: medium (CVSS 5.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-29 · updated 2026-10-30
Weakness: CWE-130

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 3.5.10, 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.

Affected products

mariadb-corporation mariadb-connector-j: from 3.0.0, < 3.3.7; from 3.4.0, < 3.4.5; from 3.5.0, < 3.5.10

References

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