Skip to main content
Public proof of conceptFix available

CVE-2023-42818

A public proof of concept exists; no exploitation attested.

  • Published2023-09-27
  • Fixed in3.6.5+incompatible · 3.5.6+incompatible
  • WeaknessCWE-287 · CWE-307

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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.

Timeline

dates in UTC
  1. 2023-09-2721:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-11-03 21:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2023-42818?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2023-42818?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

OSV · NVD · CISA-ADP
jumpserver/jumpserver
BranchAffectedFixed in
3.6≥ 3.6.0+incompatible, < 3.6.5+incompatible3.6.5+incompatible
3.5< 3.5.6+incompatible3.5.6+incompatible
Fit2cloud jumpserver
BranchAffectedFixed in
3.6≥ 3.6.0, < 3.6.53.6.5
3.5< 3.5.63.5.6
Jumpserver
BranchAffectedFixed in
3.6≥ 3.6.0, < 3.6.53.6.5
3.5< 3.5.63.5.6

1 more product in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Products declared by the CNA1 product

As GitHub_M, the CNA that assigned this CVE, declared them in the CVE record; versions as written.

  • jumpserver
    Affected
    • = >= 3.6.0, < 3.6.5no fix stated
    • = < 3.5.6no fix stated

Source: the CNA record (CVE Program), © The MITRE Corporation,CVE Terms of UseCVE recordupdated 2025-03-25

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • govulncheck-vulndbopenSUSE:Tumbleweedall versions · fixed in 0.0.20250612T141001-1.1

Full record on NVD

Fix

  1. Update jumpserver/jumpserver to 3.6.5+incompatible · 3.5.6+incompatible

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub
Metasploit modules
none listed
Metasploit Framework

Sources

  • CISA-ADPSSVC decisionpoc2024-09-23
  • OpenCVESSVC decisionpoc—
  • CNACVSS 3.15.4known since 2026-10-23
  • NVDCVSS 3.19.8read 2026-10-23
  • CNAweakness (CWE)CWE-287known since 2026-10-23
  • NVDweakness (CWE)CWE-307read 2026-10-23
  • FIRST EPSSEPSS score0.7 %2026-11-03
  • OSVaffected packages—
  • GitHub Advisoriesadvisory—

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published
2023-09-27
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-jv3c-27cv-w8jv

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.

Is CVE-2023-42818 actively exploited?

A proof-of-concept exploit exists for CVE-2023-42818, but active exploitation has not been confirmed at this time.

What is the CVSS score for CVE-2023-42818?

CVE-2023-42818 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Running jumpserver/jumpserver? Hear about its next vulnerability

Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».

Get alerts for this productCISA KEV additions, November 2026Search CVEs

No credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database

Sources for this record