CVE-2026-94029

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://lists.apache.org/thread.html/ytbl4rwby62xl7llm3wp7k975wwdx99t
http://www.openwall.com/lists/oss-security/2026/09/29/37

Configurations

No configuration.

History

30 Sep 2026, 11:16

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2026/09/29/37 -

30 Sep 2026, 10:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-30 10:17

Updated : 2026-09-30 20:17

NVD link : CVE-2026-94029

Mitre link : CVE-2026-94029

CVE.ORG link : CVE-2026-94029

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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