CVE-2023-42818

critical

Description

JumpServer is an open source bastion host. When users enable MFA and use a public key for authentication, the Koko SSH server does not verify the corresponding SSH private key. An attacker could exploit a vulnerability by utilizing a disclosed public key to attempt brute-force authentication against the SSH service This issue has been patched in versions 3.6.5 and 3.5.6. Users are advised to upgrade. There are no known workarounds for this issue.

References

https://www.sonarsource.com/blog/diving-into-jumpserver-attackers-gateway-to-internal-networks-1-2

https://github.com/jumpserver/jumpserver/security/advisories/GHSA-jv3c-27cv-w8jv

Details

Source: Mitre, NVD

Published: 2023-09-27

Updated: 2026-06-17

Risk Information

CVSS v2

Base Score: 10

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Severity: Critical

CVSS v3

Base Score: 9.8

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity: Critical

EPSS

EPSS: 0.00294