Improper Certificate Validation in IntelliJ IDEA - CVE-2026-123306
Published: November 6, 2026
Vulnerability identifier: #VU159672
CSH Severity: Medium
CVSS v4: 9.1 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-123306
CWE-ID: CWE-295
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to bypass server certificate validation, potentially enabling server impersonation.
The vulnerability exists due to improper certificate validation in IntelliJ IDEA's server certificate handling when running in headless mode. A remote attacker can cause an untrusted server certificate to be added to the trust store to undermine server authentication.
Affected software
IntelliJ IDEA
How to mitigate CVE-2026-123306
Install security update from vendor's website.
IntelliJ IDEA - update to 2026.3