CVE-2026-42778 — mina-core
CRITICALCVE-2026-42778 is a critical-severity (CVSS 9.8) Deserialization of Untrusted Data vulnerability in org.apache.mina:mina-core. A fix is available for org.apache.mina:mina-core — see the affected versions and patch details below.
Apache MINA: CWE-502 Deserialization of Untrusted Data (take 2)
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-42778.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
org.apache.mina:mina-core☕org.apache.mina:mina-coreReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
The fix for CVE-2026-41409 was not applied to the 2.1.X and 2.2.X branches. Here was the original issue description:
The fix for CVE-2024-52046 in Apache MINA AbstractIoBuffer.getObject() was incomplete. The classname allowlist of classes allowed to be deserialized was applied too late after a static initializer in a class to be read might already have been executed.
Affected versions are Apache MINA 2.1.0 <= 2.1.11, and 2.2.0 <= 2.2.6.
The problem is resolved in Apache MINA 2.1.12, and 2.2.7 by applying the classname allowlist earlier.
Affected are applications using Apache MINA that call IoBuffer.getObject().
Applications using Apache MINA are advised to upgrade
The fix for CVE-2024-52046 in Apache MINA AbstractIoBuffer.getObject() was incomplete. The classname allowlist of classes allowed to be deserialized was applied too late after a static initializer in a class to be read might already have been executed.
Affected versions are Apache MINA 2.1.0 <= 2.1.110, and 2.2.0 <= 2.2.6.
The problem is resolved in Apache MINA 2.1.12, and 2.2.7 by applying the classname allowlist earlier.
Affected are applications using Apache MINA that call IoBuffer.getObject().
Applications using Apache MINA are advised to upgrade
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.apache.mina:mina-core | ≥ 2.1.0&&< 2.1.12 | 2.1.12org.apache.mina:mina-core:2.1.12 |
| ☕Maven | org.apache.mina:mina-core | ≥ 2.2.0&&< 2.2.7 | 2.2.7org.apache.mina:mina-core:2.2.7 |
Affected Products
minaapacheDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.mina:mina-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.mina:mina-core to 2.1.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-42778 is resolved across your whole dependency graph.
Workarounds
Do not deserialise data from untrusted sources: where the format allows it, restrict deserialisation to an explicit allowlist of expected types, and prefer a data-only format (JSON, Protobuf) over one that can reconstruct arbitrary objects until you can upgrade.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Red Hat products are affected by this vulnerability. However, the vulnerable code cannot be reached and therefore are not vulnerable. Due to this reason, this flaw has been rated with a low severity.
| Product | Fixed in | Advisory |
|---|---|---|
| OpenShift Developer Tools and Services 4.12 | ocp-tools-4/jenkins-rhel8:1786628667 | RHSA-2026:60247 |
| OpenShift Developer Tools and Services 4.13 | ocp-tools-4/jenkins-rhel8:1786628681 | RHSA-2026:60249 |
| OpenShift Developer Tools and Services 4.14 | ocp-tools-4/jenkins-rhel8:1786533561 | RHSA-2026:60248 |
| OpenShift Developer Tools and Services 4.15 | ocp-tools-4/jenkins-rhel8:1786533565 | RHSA-2026:60239 |
| OpenShift Developer Tools and Services 4.16 | ocp-tools-4/jenkins-rhel9:1787125166 | RHSA-2026:60251 |
| OpenShift Developer Tools and Services 4.17 | ocp-tools-4/jenkins-rhel9:1787124635 | RHSA-2026:60246 |
| OpenShift Developer Tools and Services 4.18 | ocp-tools-4/jenkins-rhel9:1787125069 | RHSA-2026:60250 |
| OpenShift Developer Tools and Services 4.19 | ocp-tools-4/jenkins-rhel9:1787124632 | RHSA-2026:60252 |
Frequently Asked Questions
Is CVE-2026-42778 in your dependencies?
Find it across Maven, including transitive dependencies.