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CVE-2023-42818

Status: ModifiedCritical (9.8)—

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

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (1)

Fit2cloud — Jumpserver

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2023-42818",
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          "version": "2.0.3",
          "timestamp": "2024-09-23T18:52:26.646507Z"
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          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L",
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  "published": "2023-09-27T21:15:10.173",
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    }
  ],
  "lastModified": "2026-06-17T06:24:35.167",
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