All vulnerabilities
CVE-2026-94029

Apache MINA SSHD: Memory exhaustion in SFTP v6 check-file-name/check-file-handle extension

Apache Software Foundation Apache MINA SSHD
Open in ThreatlineRecord JSON
CVSS
6.5Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.38%Chance of exploitation activity in the next 30 days, higher than 30% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in2.20.0Also 3.0.0-M6CVE List
Published30 Sep 2026Updated 30 Sep 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

Server-side memory exhaustion in Apache MINA SSHD 1.0.0 to 2.19.0 and 3.0.0-M1 to 3.0.0-M5, component sshd-sftp, in the SFTP v6 check-file-name/check-file-handle extension. Apache MINA SSHD is a Java library for client-side and server-side SSH.

Using a very small "block size" (for instance 256, which is the minimum) on a huge file generates many (file size / block size) hashes. The resulting SFTP reply message was accumulated fully in memory server-side, which could, with a suitably large (possibly sparse) file exhaust the server-side memory, taking down the server.

Users are recommended to upgrade to version 2.20.0 or 3.0.0-M6, which fix this issue by imposing a maximum limit on the size of the reply. Many SFTP implementations have a general limit on the size of SFTP messages anyway; typically 256kB as in OpenSSH or also in Apache MINA SSHD.

Text from CVE List

Affected versions 2

  • Apache MINA SSHDaffected: 1.0.0 before 2.20.0CVE List
  • Apache MINA SSHDaffected: 3.0.0-M1 before 3.0.0-M6CVE List

References 1