CVE-2026-55857: MariaDB Connector/J cleartext password transmission in PAM authentication

CVE-2026-55857 · Severity: medium · CVSS 5.9 · Published 2026-08-28

MariaDB Connector/J is a JDBC driver used by Java applications to connect to MariaDB databases. When using PAM (dialog) authentication over an unencrypted connection, an attacker positioned on the network path can force the driver to send database account passwords in cleartext, allowing credential theft and unauthorized database access. This occurs by default in unmodified installations connecting over plain TCP.

Technologies: MariaDB Connector/J, org.mariadb.jdbc:mariadb-java-client (Maven). Vendors: Mariadb, Maven.

Quick answers

Is CVE-2026-55857 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-55857 being exploited in the wild.
How severe is CVE-2026-55857?
Medium severity, with a CVSS score of 5.9, published 28 August 2026.
Which products and versions are affected?
MariaDB Connector/J < 2.7.14, >= 3.0.0 and < 3.3.5, >= 3.4.0 and < 3.4.3, >= 3.5.0 and < 3.5.9; org.mariadb.jdbc:mariadb-java-client (Maven) ECOSYSTEM:introduced=0,fixed=2.7.14.
Is there a fix for CVE-2026-55857?
Yes. org.mariadb.jdbc:mariadb-java-client (Maven): upgrade to 2.7.14 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-55857 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-55857?
Check whether you run MariaDB Connector/J or org.mariadb.jdbc:mariadb-java-client (Maven) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • org.mariadb.jdbc:mariadb-java-client (Maven): upgrade to 2.7.14 or later
    # set org.mariadb.jdbc:mariadb-java-client to 2.7.14 in your pom.xml or build.gradle

Technical details

The vulnerability is a cleartext transmission of credentials (CWE-319, CWE-522) in the PAM authentication handler (SendPamAuthPacketFactory). The driver's mysql_clear_password plugin was correctly gated to require secure transport (TLS or Unix socket), but the PAM plugin inherited a default value permitting cleartext transmission over plain TCP. An attacker or MITM server can trigger an Authentication Switch Request to negotiate the dialog plugin, causing the driver to respond with the user's cleartext password. The root cause is missing secure-transport enforcement in the PAM handler. Attack preconditions: unencrypted connection (sslMode=DISABLE by default), no plugin whitelist (restrictedAuth=null by default), and MITM capability or connection to attacker-controlled server. Patches enforce PAM to require TLS or Unix socket, identical to mysql_clear_password policy. Fixed in versions 2.7.14, 3.3.5, 3.4.3, and 3.5.9.

Affected products

  • MariaDB Connector/J < 2.7.14, >= 3.0.0 and < 3.3.5, >= 3.4.0 and < 3.4.3, >= 3.5.0 and < 3.5.9

Identifiers

  • CVE-2026-55857
  • GHSA-qxvw-fvwx-5cp7

Timeline

  • 2026-08-28: disclosed: Advisory published on GitHub
  • 2026: patched: Fixed in versions 2.7.14, 3.3.5, 3.4.3, and 3.5.9

References

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