Cyber Resilience

CVE-2025-42921

Jetbrains Toolbox ≤ 2.6

Published
17 April 2025
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 4.2
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
EPSS Score 0.0019 9th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2025-42921 is a medium-severity Improper Validation of Certificate with Host Mismatch (CWE-297) vulnerability in Jetbrains Toolbox. Its CVSS base score is 4.2 (Medium).

Operationally, ranked at the 9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-23 (Session Authenticity) and SC-8 (Transmission Confidentiality and Integrity) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

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

CWE(s)

Related Threats

CVEs Like This One

CVE-2025-43012Same product: Jetbrains Toolbox
CVE-2025-43013Same product: Jetbrains Toolbox
CVE-2025-43014Same product: Jetbrains Toolbox
CVE-2024-24943Same product: Jetbrains Toolbox
CVE-2023-39175Same vendor: Jetbrains
CVE-2024-54156Same vendor: Jetbrains
CVE-2025-64684Same vendor: Jetbrains
CVE-2025-54538Same vendor: Jetbrains
CVE-2024-47950Same vendor: Jetbrains
CVE-2024-39879Same vendor: Jetbrains

Affected Assets

jetbrains
toolbox
≤ 2.6

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SC-23 Session Authenticity
  • SC-8 Transmission Confidentiality and Integrity
  • IA-3 Device Identification and Authentication
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V17.2.8

Mitigating Controls (NIST 800-53 r5) AI

prevent

Host key verification directly enforces session authenticity for SSH connections, preventing MITM by ensuring the remote endpoint identity matches the expected key.

prevent

Missing host verification allows integrity compromise of the SSH channel; SC-8 requires cryptographic protection of transmission integrity for remote sessions.

prevent

Requires unique identification and authentication of devices (the SSH server) prior to establishing the connection, which host key checking implements.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.DS-02 mostly match
prevents

Protecting data-in-transit integrity depends on proper certificate validation to prevent MITM.

PR.PS-06 mostly match
prevents

Secure development practices include coding correct certificate validation logic.

PR.AA-03 partial match
prevents

Server/service authentication via certificates directly requires correct host validation.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing can detect missing certificate validation and host-mismatch checks.

degrades

Network security controls include certificate validation and host-name verification to prevent man-in-the-middle attacks.

degrades

Security of network services requires proper TLS configuration and certificate validation for service endpoints.

prevents

Use of cryptography mandates correct implementation of certificate validation and hostname verification.

prevents

Application security requirements include secure communication and certificate validation for external services.

mitigates

Secure system architecture principles require proper certificate validation to protect communications.

References