CVE-2023-42818
SSH public key login without private key challenge if mfa is enabled in jumpserver
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
SSH public key login without private key challenge if mfa is enabled in jumpserver
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.
- Record
CVE-2023-42818- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L - Weakness
- CWE-287
- Updated
- 2026-11-02
EUVDEUVD-2023-47240
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.
- Record
EUVD-2023-47240- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L - Updated
- 2026-11-02
NVD
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.
- Record
CVE-2023-42818- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-287, CWE-307
- Updated
- 2026-11-02
OSV
SSH public key login without private key challenge if mfa is enabled in jumpserver
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.
- Record
CVE-2023-42818- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L - Weakness
- CWE-287
- Updated
- 2026-11-02
OSVGO-2025-3570 No score
SSH public key login without private key challenge if mfa is enabled in jumpserver in github.com/jumpserver/koko in github.com/jumpserver/jumpserver
SSH public key login without private key challenge if mfa is enabled in jumpserver in github.com/jumpserver/koko in github.com/jumpserver/jumpserver
- Record
GO-2025-3570- Updated
- 2026-11-02
OSVopenSUSE-SU-2025:15225-1 No score
govulncheck-vulndb-0.0.20250612T141001-1.1 on GA media
These are all security issues fixed in the govulncheck-vulndb-0.0.20250612T141001-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2025:15225-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
github.com/jumpserver/kokoGo |
All versions | None known |
github.com/jumpserver/jumpserverGo |
before 3.5.6+incompatible, 3.6.0+incompatible up to 3.6.5+incompatible | 3.5.6+incompatible3.6.5+incompatible |
govulncheck-vulndbopenSUSE:Tumbleweed From an advisory covering 29 CVEs |
before 0.0.20250612T141001-1.1 | 0.0.20250612T141001-1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2023-42818 is a medium vulnerability (CVSS 5.4) in Fit2cloud Jumpserver, published September 27, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.68%, the 52nd percentile. Fixed in github.com/jumpserver/jumpserver 3.5.6+incompatible.
References
github.com/jumpserver/jumpserver/security/advisories/GHSA-jv3c-27cv-w8jv
sonarsource.com/blog/diving-into-jumpserver-attackers-gateway-to-internal-networks-1-2
nvd.nist.gov/vuln/detail/CVE-2023-42818
suse.com/security/cve/CVE-2020-36846
Show 27 moreShow less