CVE-2026-47065: Apache MINA: Critical Deserialization Allow-list Bypass via resolveProxyClass

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 0.5%, percentile 42: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 42% of all scored CVEs (low). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes org.apache.mina:mina-core (Maven) >= 2.2.0, < 2.2.8, fixed in 2.2.8; org.apache.mina:mina-core (Maven) >= 2.1.0, < 2.1.13, fixed in 2.1.13; org.apache.mina:mina-core (Maven) < 2.0.29, fixed in 2.0.29. Check your lockfile, including transitive dependencies.

What it is

ZDRES-232: resolveProxyClass Not Overridden - acceptMatchers Filter Bypass via java.lang.reflect.Proxy Assessment: Fully addressed. When the serialised stream contains a TCPROXYCLASSDESC (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 of SomeClass — and many real-world classes have side-effecting static initialisers Both issues have been fixed.

From the GitHub advisory

ZDRES-232: resolveProxyClass Not Overridden - acceptMatchers Filter Bypass via java.lang.reflect.Proxy

Assessment: Fully addressed.

When the serialised stream contains a TCPROXYCLASSDESC (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.

Weakness type: CWE-502.

Product: org.apache.mina:mina-core (Maven) · Assigned by: apache · Published: 2026-06-03

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: none
• Scope: unchanged

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
• FIRST EPSS (model of 2026-10-21): 0.50% probability of exploitation activity in the next 30 days; percentile 42.

Timeline

• 2026-06-03 — CVE record published by apache
• 2026-06-03 — GitHub-reviewed advisory GHSA-v3pr-hxpr-mfm8 published (critical)
• 2026-06-04 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vendor and project advisories, patches

1. lists.apache.org lists.apache.org

Vulnerability records

1. GitHub Advisory GHSA-v3pr-hxpr-mfm8 github.com
2. CVE.org record CVE-2026-47065 cve.org
3. NVD entry CVE-2026-47065 nvd.nist.gov

Critical Maven advisories · Today’s Security Digest