CVE-2021-29263: 
JetBrains IntelliJ IDEA vulnerability analysis and mitigation

In JetBrains IntelliJ IDEA 2020.3.3, a vulnerability was discovered that allowed local code execution due to insufficient checks when getting projects from Version Control System (VCS). The vulnerability was identified as CVE-2021-29263 and was fixed in IntelliJ IDEA version 2020.3.3 (JetBrains Blog, Debian Tracker).

The vulnerability was classified as medium severity and involved code execution without user confirmation for untrusted projects. The issue stemmed from insufficient security checks during the process of obtaining projects from Version Control Systems. Multiple related issues were tracked under IDEA-260911, IDEA-260912, IDEA-260913, IDEA-261846, IDEA-261851, IDEA-262917, IDEA-263981, and IDEA-264782 (JetBrains Blog).

The vulnerability allowed unauthorized local code execution when cloning or checking out a Gradle project from an external repository. If an attacker could convince a developer to clone or check out a malicious repository, they could execute arbitrary code as part of the repository clone or checkout operation (GitHub Security Lab).

The vulnerability could be exploited when cloning or checking out a repository containing a Gradle project. Android Studio and IntelliJ would run the build task immediately without requesting user confirmation, preventing users from analyzing the build script. Attackers could hide malicious code within Gradle's Exec tasks or implement more stealthy approaches (GitHub Security Lab).

The vulnerability was addressed in IntelliJ IDEA version 2020.3.3, released on March 16, 2021. Users were advised to upgrade to this version or later to protect against this security issue (GitHub Security Lab).