CVE-2023-42818

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.

CVSS Metrics

• v3.1•MEDIUM•Score: 5.4CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L
• v3.1•CRITICAL•Score: 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Trends

Current EPSS score: 0.17%• Percentile: 39%

Techniques & Countermeasures

• CWE-287•Improper Authentication

  When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

• CWE-307•Improper Restriction of Excessive Authentication Attempts

  The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame.

Affected Systems

• fit2cloud•jumpserver

  < 3.5.6 | ≥ 3.6.0, < 3.6.5

• github.com/jumpserver•jumpserver

  ≥ 3.6.0+incompatible, < 3.6.5+incompatible

• github.com/jumpserver•koko

  all

• jumpserver•jumpserver

  ≥ 3.6.0, < 3.6.5 | < 3.5.6

References (3)

• https://github.com/jumpserver/jumpserver/security/advisories/GHSA-jv3c-27cv-w8jv
• https://www.sonarsource.com/blog/diving-into-jumpserver-attackers-gateway-to-internal-networks-1-2
• https://nvd.nist.gov/vuln/detail/CVE-2023-42818