Deserialization in Apache Mina

CVE-2026-41635

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 if the class is present in the accepted class filter before calling Class.forName().  Affected versions are Apache MINA 2.0.0 <= 2.0.27, 2.1.0 <= 2.1.10, and 2.2.0 <= 2.2.5. The problem is resolved in Apache MINA 2.0.28, 2.1.11, and 2.2.6 by applying the classname allowlist earlier. Affected are applications using Apache MINA that call  IoBuffer.getObject(). Applications using Apache MINA are advised to upgrade.

Vulnerability class: Insecure Deserialization

Published · last modified .

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.

EPSS exploit prediction

EPSS: 0.008 (56.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 57th percentile — 56.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-41635: held from 0.006 to 0.008.

EPSS over last 30 days · oldest: 0.006 · newest: 0.008 · change: +0.002

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-41635?
CVE-2026-41635 is a critical-severity vulnerability in Apache Mina, classified under Deserialization of Untrusted Data. CVSS score: 9.8/10. Published 2026-04-27.
How severe is CVE-2026-41635?
Critical severity. CVSS v3 base score is 9.8 out of 10.