CVE-2026-94029: Apache Software Foundation Apache Mina Sshd

Medium severity, CVSS 6.5. EPSS: 0.4% chance of exploitation in the next 30 days.

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.

Affected products

• Apache Software Foundation Apache Mina Sshd: from 1.0.0, before 2.20.0 (fixed in 2.20.0); from 3.0.0-M1, before 3.0.0-M6 (fixed in 3.0.0-M6)

Published 2026-09-30. Last modified 2026-09-30.