CVE-2026-123841 in IntelliJ IDEA
Summary
by MITRE • 11/06/2026
In JetBrains IntelliJ IDEA before 2026.3 code execution was possible via symlinks in an imported settings archive
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Analysis
by VulDB Data Team • 11/06/2026
The vulnerability identified in versions of JetBrains IntelliJ IDEA prior to version 2026.3 represents a significant security flaw related to the handling of external configuration archives during the import process. This issue stems from improper validation and sanitization of file paths within archived files, specifically allowing for symlink traversal attacks. When users attempt to import settings or configurations from an archive file into the IDE, the application fails to adequately restrict access to resources outside the intended directory structure. By exploiting this weakness, a malicious actor can craft an archive containing symbolic links that point to arbitrary locations on the host system's filesystem.
From a technical perspective, the core of this vulnerability lies in the lack of strict path canonicalization and containment checks during the extraction phase. When IntelliJ IDEA processes the imported settings archive, it resolves these symlinks without verifying whether they reference files within a safe or expected scope. This behavior mirrors common directory traversal vulnerabilities where an attacker leverages relative paths such as dot-dot-slash sequences to escape sandboxed directories. In this specific context, however, the mechanism is more direct through the use of symbolic links rather than just path manipulation strings. The IDE's internal logic assumes that all files within a settings archive are benign and intended for local configuration storage, thereby bypassing standard security boundaries designed to prevent unauthorized file access or modification.
The operational impact of this vulnerability is severe due to its potential for arbitrary code execution. If an attacker can trick a user into importing a maliciously crafted settings archive, the resulting symlink resolution could allow the writing of executable scripts or binaries into directories that are automatically executed by the IDE upon startup or during specific operations. For instance, if symlinks point to locations where IntelliJ IDEA loads plugins, run configurations, or other auto-executed components, an attacker can effectively inject malicious code that runs with the privileges of the user launching the application. This could lead to full system compromise, data exfiltration, or the installation of persistent backdoors on the victim's machine. The risk is particularly acute in enterprise environments where shared settings profiles might be distributed via untrusted channels or automated deployment tools that do not strictly validate archive contents.
This vulnerability aligns with CWE-59 Improper Link Resolution Before File Access, as it involves the failure to properly resolve symbolic links before performing file operations. It also relates to CWE-22 Path Traversal: Outside Current Directory With Symlink Attack, highlighting how link resolution can be abused to bypass directory restrictions. From an offensive security standpoint, this behavior is consistent with techniques found in MITRE ATT&CK framework under the category of Initial Access or Execution, specifically involving user interaction and potentially file manipulation tactics like T1059 Command and Scripting Interpreter if malicious scripts are executed via the compromised configuration files.
To mitigate this risk, organizations must ensure that all instances of IntelliJ IDEA are updated to version 2026.3 or later, where these path validation mechanisms have been hardened. Administrators should enforce strict policies regarding the sourcing of settings archives and discourage users from importing configurations from unverified third-party sources. Additionally, implementing application control solutions can help prevent unauthorized executables from running in directories associated with IDE operations. Security awareness training is also critical to educate developers on the risks of opening configuration files or archives received via email or other communication channels without prior verification. Until patches are applied, limiting file system permissions for IntelliJ IDEA processes and disabling automatic loading of certain plugin types can provide additional layers of defense against exploitation attempts.