What is CVE-2023-42442?

CVE-2023-42442 is a high-severity vulnerability in Fit2cloud Jumpserver, classified under Improper Authentication. CVSS score: 8.2/10. Published 2023-09-15.

How severe is CVE-2023-42442?

High severity. CVSS v3 base score is 8.2 out of 10.

Is CVE-2023-42442 known to be exploited?

44 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Auth bypass in Fit2cloud Jumpserver

CVE-2023-42442

JumpServer is an open source bastion host and a professional operation and maintenance security audit system. Starting in version 3.0.0 and prior to versions 3.5.5 and 3.6.4, session replays can download without authentication. Session replays stored in S3, OSS, or other cloud storage are not affected. The api `/api/v1/terminal/sessions/` permission control is broken and can be accessed anonymously. SessionViewSet permission classes set to `[RBACPermission | IsSessionAssignee]`, relation is or, so any permission matched will be allowed. Versions 3.5.5 and 3.6.4 have a fix. After upgrading, visit the api `$HOST/api/v1/terminal/sessions/?limit=1`. The expected http response code is 401 (`not_authenticated`).

Vulnerability class: Broken Authentication

Published 2023-09-15 · last modified 2026-06-17.

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:N/I:L/A:H.

EPSS exploit prediction

EPSS: 0.630 (99.2th percentile), scored 2026-10-18.

High probability of exploitation in the next 30 days — patch promptly. 99th percentile — 99.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.585 · newest: 0.630 · change: +0.045

Affected products

Fit2cloud Jumpserver
Jumpserver — versions >= 3.0.0, < 3.5.5, >= 3.6.0, < 3.6.4

Weakness classification (CWE)

CWE-287 — Improper Authentication

Public proof-of-concept exploits

References

github.com/jumpserver/jumpserver/security/advisories/GHSA-633x-3f4f-v9rw (Exploit, Vendor Advisory)
github.com/jumpserver/jumpserver/commit/0a58bba59cd275bab8e0ae58bf4b359fbc5eb74a (Patch)
github.com/jumpserver/jumpserver/blob/v3.6.1/apps/terminal/api/session/session… (Product)

Frequently asked questions

What is CVE-2023-42442?: CVE-2023-42442 is a high-severity vulnerability in Fit2cloud Jumpserver, classified under Improper Authentication. CVSS score: 8.2/10. Published 2023-09-15.
How severe is CVE-2023-42442?: High severity. CVSS v3 base score is 8.2 out of 10.
Is CVE-2023-42442 known to be exploited?: 44 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.