Excessive Iteration in OpenSSH - #VU158349
Published: October 28, 2026
Vulnerability identifier: #VU158349
CSH Severity: Medium
CVSS v4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-834
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to potentially cause a denial of service through excessive CPU consumption while a private key is processed.
The vulnerability exists due to excessive iteration in OpenSSH private key processing in ssh-keygen, ssh, and sshd when an OpenSSH-format key specifies an extremely high number of key derivation rounds. A remote attacker can supply a crafted private key to a process that accepts it for loading to make key derivation consume excessive processing time.
Affected software
OpenSSH
Remediation
Install security update from vendor's website.
OpenSSH - update to 10.6p1