CVE-2021-26028: 
PHP vulnerability analysis and mitigation

A path traversal vulnerability was discovered in Joomla! versions 3.0.0 through 3.9.24, identified as CVE-2021-26028. The vulnerability was reported on September 8, 2020, and fixed on March 2, 2021. The issue allows an attacker to write files outside of the intended path when extracting a specifically crafted zip package (Joomla Advisory).

The vulnerability is classified as a path traversal issue (CWE-22) with a CVSS v3.1 base score of 5.5 (Medium), with the vector string CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N. The vulnerability affects the Joomla archive zip class and could allow unauthorized file writing operations outside the intended directory structure (NVD).

When exploited, this vulnerability could allow an attacker to write files outside of the intended path during zip file extraction operations, potentially leading to unauthorized file system access and manipulation (Joomla Advisory).

The vulnerability requires local access and user interaction to exploit. The attack complexity is considered low, but no privilege is required to execute the attack. There have been no publicly reported instances of this vulnerability being exploited in the wild (NVD).

The vulnerability was addressed in Joomla! version 3.9.25. Users running affected versions should upgrade to version 3.9.25 or later to mitigate this security issue (Joomla Advisory).