Deserialization in Apache Mina
CVE-2026-47065
ZDRES-232: resolveProxyClass Not Overridden - acceptMatchers Filter Bypass via java.lang.reflect.Proxy Assessment: Fully addressed. When the serialised stream contains a TC_PROXYCLASSDESC (the marker for a java.lang.reflect.Proxy ), JDK’s ObjectInputStream.readProxyDesc() is dispatched. JDK then calls the default ObjectInputStream.resolveProxyClass(interfaces) implementation, which performs Class.forName(intf, false, latestUserDefinedLoader()) for EACH interface name and constructs the proxy class — bypassing the accepted classes list . ZDRES-233: Class.forName(name, initialize=true, classLoader) in readClassDescriptor Triggers Static Initialiser of Allow-Listed Classes Assessment: Fully addressed. For ANY class on the allow-list, deserialising a stream that names it triggers the class’s (static initialiser) BEFORE any instance is constructed. This means an attacker who supplies a class name on the allow-list (e.g., the developer wrote accept(“com.myapp.*") , attacker supplies com.myapp.SomeClass ) causes <clinit> of SomeClass — and many real-world classes have side-effecting static initialisers Both issues have been fixed.
Vulnerability class: Insecure Deserialization
EPSS: 0.005 (41.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Apache Mina — versions 2.0.29, 2.1.13, 2.2.8
- Apache Software Foundation Mina — versions 2.2.0, 2.1.0, 2.0.0
Weakness classification (CWE)
References
- security@apache.org (vendor-advisory, Mailing List, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-47065?
- CVE-2026-47065 is a critical-severity vulnerability in Apache Mina, classified under Deserialization of Untrusted Data. CVSS score: 9.8/10. Published 2026-06-03.
- How severe is CVE-2026-47065?
- Critical severity. CVSS v3 base score is 9.8 out of 10.