CVE-2020-4053: 
Helm vulnerability analysis and mitigation

CVE-2020-4053 affects Helm versions greater than or equal to 3.0.0 and less than 3.2.4. The vulnerability was discovered in the Helm plugin installation process, specifically when installing plugins from tar archives over HTTP. The issue was disclosed on June 15, 2020, and was patched in Helm version 3.2.4 (Helm Release, NVD).

The vulnerability is a path traversal attack (CWE-22) that occurs during the plugin installation process. When installing Helm plugins from a tar archive over HTTP, the system fails to properly validate file paths within the archive. This allows a malicious plugin author to inject a relative path into a plugin archive and copy files outside of the intended directory (Vendor Advisory). The vulnerability has received varying CVSS scores: NIST NVD assigned a base score of 6.8 (MEDIUM) with vector CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H, while GitHub assigned a score of 3.7 (LOW) with vector CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N (NVD).

The vulnerability could allow attackers to gain access to parts of the file system outside of the target folder where plugin files should reside. This could lead to information disclosure, and in more severe cases, attackers could potentially overwrite executable files or configuration files. If exploited successfully, this could result in Remote Command Execution on the victim's machine (Vendor Advisory).

The vulnerability requires a malicious plugin author to create a specially crafted tar archive that includes relative paths designed to write files outside the intended directory. The attack requires user interaction as they must explicitly install the malicious plugin (Vendor Advisory).

The vulnerability was fixed in Helm version 3.2.4. The fix includes improved path validation and cleaning in the plugin installation process. Users are strongly encouraged to upgrade to version 3.2.4 or later to receive the security patch (Helm Release, Vendor Advisory).