# CVE-2026-94029: Apache MINA SSHD memory exhaustion in SFTP check-file extension

Source: https://junglewise.ai/threats/cve-2026-94029-server-side-memory-exhaustion-in-apache-mina-sshd-1-0-0-to-2-19-0  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-30. Updated: 2026-09-30  
License: CC BY 4.0 with a link back

CVE-2026-94029 · Severity: medium · CVSS 6.5 · Published 2026-09-30

Apache MINA SSHD is a Java library providing SSH client and server functionality. An attacker can exhaust server memory by requesting hashes of huge files with minimal block sizes, causing the SFTP reply to accumulate unbounded in memory and potentially crash the server.

Technologies: [Apache MINA SSHD](https://junglewise.ai/threats/technologies/mina-sshd). Vendors: [Apache](https://junglewise.ai/threats/vendors/apache).

## Quick answers

**Is CVE-2026-94029 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-94029 being exploited in the wild.

**How severe is CVE-2026-94029?** Medium severity, with a CVSS score of 6.5, published 30 September 2026.

**Which products and versions are affected?** Apache MINA SSHD 1.0.0 to 2.19.0, 3.0.0-M1 to 3.0.0-M5.

**Is there a fix for CVE-2026-94029?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-94029 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-94029?** Check whether you run Apache MINA SSHD at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a denial-of-service condition in the SFTP v6 check-file-name/check-file-handle extension. When processing a check-file request with a very small block size (minimum 256 bytes) on a large file, the server generates many hashes and accumulates the entire SFTP reply message in memory without enforcing a size limit, allowing remote attackers to trigger memory exhaustion and crash the service.

## Affected products

- Apache MINA SSHD 1.0.0 to 2.19.0, 3.0.0-M1 to 3.0.0-M5

## Timeline

- 2026-09-30: disclosed

## References

- [https://repo.maven.apache.org/maven2](https://repo.maven.apache.org/maven2)
- [https://lists.apache.org/thread.html/ytbl4rwby62xl7llm3wp7k975wwdx99t](https://lists.apache.org/thread.html/ytbl4rwby62xl7llm3wp7k975wwdx99t)

## Related threats

- [Apache MINA SSHD LDAP injection authentication bypass](https://junglewise.ai/threats/cve-2026-94053-authentication-bypass-via-ldap-injection-in-component-sshd-ldap)
- [Apache MINA SSHD authentication bypass in LdapPasswordAuthenticator](https://junglewise.ai/threats/cve-2026-94052-a-missing-check-in-ldappasswordauthenticator-in-component-sshd)
- [Apache MINA SSHD memory exhaustion in SFTP client](https://junglewise.ai/threats/cve-2026-94002-possible-memory-exhaustion-in-sftp-clients-defaultsftpclient-in)
- [Apache MINA SSHD denial of service via SCP protocol line length](https://junglewise.ai/threats/cve-2026-93996-uncontrolled-resource-consumption-in-component-ssd-scp-in-apache)
- [Apache MINA SSHD improper input validation in sshd-git](https://junglewise.ai/threats/cve-2026-93995-improper-input-validation-in-sshd-git-in-apache-mina-sshd)