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Security Alerts

CVE-2026-42779: Deserialization allowlist bypass in Apache MINA (2.1.X/2.2.X)

The fix for CVE-2026-41635 was not applied to the 2.1.X and 2.2.X branches. AbstractIoBuffer.resolveClass() in Apache MINA contains two branches; one (for static classes/primitive types) does not check the class at all, bypassing the allowlist.

Summary

ParameterValue
CVE IDCVE-2026-42779
Alert SourceGitHub Advisory - Critical Vulnerability
CVE Publication Year2026
Date Published2026-05-01
VendorApache Software Foundation
ProductApache MINA
CVSS Score9.8 (critical)
EPSS Score0.0% (percentile: 14%)
CISA KEVNo
RansomwareNot confirmed

Vulnerability Description

The fix for CVE-2026-41635 was not applied to the 2.1.X and 2.2.X branches. Original issue description:

Apache MINA’s AbstractIoBuffer.resolveClass() contains two branches; one of them (for static classes or primitive types) does not check the class at all, bypassing the classname allowlist and allowing arbitrary code to be executed.

The fix checks whether the class is present in the accepted class filter before calling Class.forName().

Affected versions include Apache MINA in the 2.1.X branch (<= 2.1.11) and 2.2.X branch (<= 2.2.6); a fix is available in the corresponding newer releases.

Required Actions

Update Apache MINA to a release that contains the fix on both branches: 2.1.X (>= 2.1.12) and 2.2.X (>= 2.2.7). Until updated, do not accept serialized data from untrusted sources and enforce a strict class-filter policy. Audit project dependencies (mvn dependency:tree, gradle dependencies) for vulnerable Apache MINA versions.

Who Is Affected?

This vulnerability affects Apache MINA by the Apache Software Foundation in the 2.1.X and 2.2.X branches. Check whether your organization uses Apache MINA as a networking library and roll out the update.

Sources


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