Multiple SQL injection vulnerabilities in Simple Machines Forum (SMF) before 1.1.15 and 2.x before 2.0.1 allow remote attackers to execute arbitrary SQL commands via vectors involving a (1) HTML entity or (2) display name. NOTE: some of these details are obtained from third party information.

Cross-site scripting (XSS) vulnerability in the EditNews function in ManageNews.php in Simple Machines Forum (SMF) before 1.1.13, and 2.x before 2.0 RC5, might allow remote authenticated users to inject arbitrary web script or HTML via a save_items action.

The PlushSearch2 function in Search.php in Simple Machines Forum (SMF) before 1.1.13, and 2.x before 2.0 RC5, uses certain cached data in a situation where a temporary table has been created, even though this cached data is intended only for situations where a temporary table has not been created, which might allow remote attackers to obtain sensitive information via a search.

The loadUserSettings function in Load.php in Simple Machines Forum (SMF) before 1.1.13, and 2.x before 2.0 RC5, does not properly handle invalid login attempts, which might make it easier for remote attackers to obtain access or cause a denial of service via a brute-force attack.

SSI.php in Simple Machines Forum (SMF) before 1.1.13, and 2.x before 2.0 RC5, does not properly restrict guest access, which allows remote attackers to have an unspecified impact via unknown vectors.

Simple Machines Forum (SMF) before 1.1.13, and 2.x before 2.0 RC5, does not properly validate the start parameter, which might allow remote attackers to conduct SQL injection attacks, obtain sensitive information, or cause a denial of service via a crafted value, related to the cleanRequest function in QueryString.php and the constructPageIndex function in Subs.php.

The password reset functionality in Simple Machines Forum (SMF) 1.0.x before 1.0.14, 1.1.x before 1.1.6, and 2.0 before 2.0 beta 4 includes clues about the random number generator state within a hidden form field and generates predictable validation codes, which allows remote attackers to modify passwords of other users and gain privileges.

Simple Machines Forum (SMF), probably 1.1.4, relies on "randomly generated static" to hinder brute-force attacks on the WAV file (aka audio) CAPTCHA, which allows remote attackers to pass the CAPTCHA test via an automated attack that considers Hamming distances. NOTE: this issue reportedly exists because of an insufficient fix for CVE-2007-3308.