HIGH · 7.3

CVE-2026-56624

Improper certificate validation in Apache MINA SSHD (server-side). Apache MINA SSHD is a Java library for client-side and server-side SSH. Server-side OpenSSH user certificate validation during us...

Vulnerability Description

Improper certificate validation in Apache MINA SSHD (server-side). Apache MINA SSHD is a Java library for client-side and server-side SSH. Server-side OpenSSH user certificate validation during user authentication in an Apache MINA SSHD server did not check for the unsupported force-command or verify-required options that could be embedded in the certificate, nor did it validate these options. As a result it was possible that a user could authenticate with such a certificate that included a force-command option but still was able to execute other commands. What other command exactly would be available to the user depends on the implementation of the server. This issue is fixed in Apache MINA SSHD 2.19.0 and 3.0.0-M5. Applications are advised to upgrade to these versions. The fix rejects OpenSSH user certificates that include these options, since Apache MINA SSHD implements neither force-command nor sk-*[email protected] user certificates (which are the only ones for which verify-required would make sense).

CVSS Score

7.3

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE

Affected Products

VendorProductVersions
ApacheMina Sshd>= 2.0.0, < 2.19.0

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-56624?

CVE-2026-56624 is a vulnerability with a CVSS score of 7.3 (HIGH). Improper certificate validation in Apache MINA SSHD (server-side). Apache MINA SSHD is a Java library for client-side and server-side SSH. Server-side OpenSSH user certificate validation during us...

How severe is CVE-2026-56624?

CVE-2026-56624 has been rated HIGH with a CVSS base score of 7.3/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-56624?

Check the references section above for vendor advisories and patch information. Affected products include: Apache Mina Sshd.