What is CVE-2025-42921?

CVE-2025-42921 is a medium-severity vulnerability in Jetbrains Toolbox, classified under Improper Validation of Certificate with Host Mismatch. CVSS score: 4.2/10. Published 2025-04-17.

How severe is CVE-2025-42921?

Medium severity. CVSS v3 base score is 4.2 out of 10.

Vulnerability in Jetbrains Toolbox

CVE-2025-42921

In JetBrains Toolbox App before 2.6 host key verification was missing in SSH plugin

Published 2025-04-17 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.2 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.002 (8.4th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 8th percentile — 8.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

Jetbrains Toolbox
Jetbrains Toolbox App — versions 0

Weakness classification (CWE)

CWE-297 — Improper Validation of Certificate with Host Mismatch

References

www.jetbrains.com/privacy-security/issues-fixed/ (Vendor Advisory)

Frequently asked questions

What is CVE-2025-42921?: CVE-2025-42921 is a medium-severity vulnerability in Jetbrains Toolbox, classified under Improper Validation of Certificate with Host Mismatch. CVSS score: 4.2/10. Published 2025-04-17.
How severe is CVE-2025-42921?: Medium severity. CVSS v3 base score is 4.2 out of 10.