How severe is CVE-2023-42818?

CVE-2023-42818 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability low.

Is CVE-2023-42818 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-42818?

CVE-2023-42818 affects Fit2cloud Jumpserver. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-42818?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-42818 published?

CVE-2023-42818 was published on 2023-09-27 and last updated on 2026-06-17.

CVE-2023-42818

CVE-2023-42818 is a medium-severity vulnerability in Fit2cloud Jumpserver with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-307.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-307
Affected product: Fit2cloud Jumpserver
Published: 2023-09-27
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2023-42818?: 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.
How severe is CVE-2023-42818?: CVE-2023-42818 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability low.
Is CVE-2023-42818 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-42818?: CVE-2023-42818 affects Fit2cloud Jumpserver. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-42818?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-42818 published?: CVE-2023-42818 was published on 2023-09-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:fit2cloud:jumpserver:*:*:*:*:*:*:*:*

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