The Codextrous B2J Contact (aka b2j_contact) extension before 2.1.13 for Joomla! allows prediction of a uniqid value based on knowledge of a time value. This makes it easier to read arbitrary uploaded files.

The Codextrous B2J Contact (aka b2j_contact) extension before 2.1.13 for Joomla! allows a rename attack that bypasses a "safe file extension" protection mechanism, leading to remote code execution.

The Codextrous B2J Contact (aka b2j_contact) extension before 2.1.13 for Joomla! allows a directory traversal attack that bypasses a uniqid protection mechanism, and makes it easier to read arbitrary uploaded files.