Auth bypass in Fit2cloud Jumpserver
CVE-2023-43652
JumpServer is an open source bastion host. As an unauthenticated user, it is possible to authenticate to the core API with a username and an SSH public key without needing a password or the corresponding SSH private key. An SSH public key should be considered public knowledge and should not used as an authentication secret alone. JumpServer provides an API for the KoKo component to validate user private key logins. This API does not verify the source of requests and will generate a personal authentication token. Given that public keys can be easily leaked, an attacker can exploit the leaked public key and username to authenticate, subsequently gaining access to the current user's information and authorized actions. This issue has been addressed in versions 2.28.20 and 3.7.1. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.008 (56.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 56.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.007 · newest: 0.008 · change: +0.001
Affected products
- Fit2cloud Jumpserver
- Jumpserver — versions >= 2.0.0, < 2.28.20, >= 3.0.0, < 3.7.1
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/jumpserver/jumpserver/security/advisories/GHSA-fr8h-xh5x-r8g9 (Exploit, Vendor Advisory)
- www.sonarsource.com/blog/diving-into-jumpserver-attackers-gateway-to-internal-n… (Technical Description)
Frequently asked questions
- What is CVE-2023-43652?
- CVE-2023-43652 is a high-severity vulnerability in Fit2cloud Jumpserver, classified under Missing Authorization. CVSS score: 8.2/10. Published 2023-09-27.
- How severe is CVE-2023-43652?
- High severity. CVSS v3 base score is 8.2 out of 10.
- Is CVE-2023-43652 known to be exploited?
- 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.