# CVE-2026-41635: Apache MINA vulnerable to Deserialization of Untrusted Data

> Attackers can execute arbitrary code via unsafe deserialization in Apache MINA when applications call IoBuffer.getObject().

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 27 Apr 2026
- **Updated:** 28 Apr 2026
- **Also known as:** CLEANSTART-2026-BK50049, CLEANSTART-2026-BT04597, CLEANSTART-2026-GO33321, CLEANSTART-2026-NP40407, CLEANSTART-2026-SQ46621, DEBIAN-CVE-2026-41635, ECHO-5717-de56-cf1a, GHSA-8297-v2rf-2p32, MINI-33rx-2crx-cv3w, MINI-5j66-6v43-7rxh, MINI-cfhm-7x6q-p5xp, MINI-f7w4-jhfc-gv7m, MINI-p2xp-hx64-x949, MINI-pg63-c64w-5r5q, MINI-r3c7-gm5x-r96q, MINI-rjxq-w348-rvqr, MINI-v2fr-fv7g-xccv, RHLW-2026-16c4875677d98603, UBUNTU-CVE-2026-41635

## What is CVE-2026-41635?

CVE-2026-41635 is a critical unsafe deserialization vulnerability in Apache MINA, published on 27 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official 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 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.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2026-41635?

6 open source packages ship an affected version, including org.apache.mina:mina-core. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `org.apache.mina:mina-core` | Maven | From 2.0.0 | 2.0.28 |
| `org.apache.mina:mina-core` | Maven | From 2.0.0 | 2.0.28 |
| `org.apache.mina:mina-core` | Maven | From 2.1.0 | 2.1.11 |
| `org.apache.mina:mina-core` | Maven | From 2.1.0 | 2.1.11 |
| `org.apache.mina:mina-core` | Maven | From 2.2.0 | 2.2.6 |
| `org.apache.mina:mina-core` | Maven | From 2.2.0 | 2.2.6 |

Products: Apache Mina.

## How do I fix CVE-2026-41635?

Upgrade org.apache.mina:mina-core to a fixed version for your release line: 2.0.28, 2.1.11 or 2.2.6.

## Is CVE-2026-41635 being exploited?

There is no known exploitation of CVE-2026-41635 in the wild and no public exploit code.

## Other vulnerabilities in Apache MINA

- [CVE-2024-52046](https://insights.sbomify.com/CVE-2024-52046/): Apache MINA: MINA applications using unbounded deserialization may allow RCE (critical 10.0)
- [CVE-2026-47065](https://insights.sbomify.com/CVE-2026-47065/): Apache MINA: Critical Deserialization Allow-list Bypass via resolveProxyClass - ZDRES-232 (critical 9.8)
- [CVE-2026-42778](https://insights.sbomify.com/CVE-2026-42778/): Apache MINA: CWE-502 Deserialization of Untrusted Data (take 2) (critical 9.8)
- [CVE-2026-42779](https://insights.sbomify.com/CVE-2026-42779/): Apache MINA vulnerable to Deserialization of Untrusted Data (CVE-2026-41635 Incomplete Fix) (critical 9.8)
- [CVE-2026-41409](https://insights.sbomify.com/CVE-2026-41409/): Apache MINA: CWE-502 Deserialization of Untrusted Data (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-41635 and fix it if it is affected.

What it is: CVE-2026-41635 is a critical unsafe deserialization vulnerability in Apache MINA, published on 27 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-41635 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.apache.mina:mina-core (Maven): affected from 2.0.0; fixed in 2.0.28
- org.apache.mina:mina-core (Maven): affected from 2.0.0; fixed in 2.0.28
- org.apache.mina:mina-core (Maven): affected from 2.1.0; fixed in 2.1.11
- org.apache.mina:mina-core (Maven): affected from 2.1.0; fixed in 2.1.11
- org.apache.mina:mina-core (Maven): affected from 2.2.0; fixed in 2.2.6
- org.apache.mina:mina-core (Maven): affected from 2.2.0; fixed in 2.2.6

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-41635/ (Markdown: https://insights.sbomify.com/CVE-2026-41635/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-41635
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-41635
- OSV: https://osv.dev/vulnerability/CVE-2026-41635

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-41635/
Summaries are generated and may contain mistakes; the official description above is the record.