SB2023102388 - Improper Authentication in JumpServer
Published: October 23, 2023 Updated: April 27, 2026
Security Bulletin ID
SB2023102388
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Improper Authentication (CVE-ID: CVE-2023-42818)
The vulnerability allows a remote attacker to brute-force MFA codes.
The vulnerability exists due to improper authentication enforcement in the Koko SSH server authentication flow when handling non-compliant SSH authentication method sequences. A remote attacker can use a specially crafted SSH client to brute-force MFA codes.
The issue can be triggered by first querying public key usability with a publickey authentication request and then invoking the keyboard-interactive method.
Remediation
Install update from vendor's website.