Wordpress 1.5 through 2.3.1 uses cookie values based on the MD5 hash of a password MD5 hash, which allows attackers to bypass authentication by obtaining the MD5 hash from the user database, then generating the authentication cookie from that hash.

wp-admin/admin-functions.php in Wordpress before 2.2.3 and Wordpress multi-user (MU) before 1.2.5a does not properly verify the unfiltered_html privilege, which allows remote attackers to conduct cross-site scripting (XSS) attacks via modified data to (1) post.php or (2) page.php with a no_filter field.

Multiple SQL injection vulnerabilities in Wordpress before 2.2.3 and Wordpress multi-user (MU) before 1.2.5a allow remote attackers to execute arbitrary SQL commands via the post_type parameter to the pingback.extensions.getPingbacks method in the XMLRPC interface, and other unspecified parameters related to "early database escaping" and missing validation of "query string like parameters."

WordPress before 2.2.2 allows remote attackers to redirect visitors to other websites and potentially obtain sensitive information via (1) the _wp_http_referer parameter to wp-pass.php, related to the wp_get_referer function in wp-includes/functions.php; and possibly other vectors related to (2) wp-includes/pluggable.php and (3) the wp_nonce_ays function in wp-includes/functions.php.

Unrestricted file upload vulnerability in WordPress before 2.2.1 and WordPress MU before 1.2.3 allows remote authenticated users to upload and execute arbitrary PHP code by making a post that specifies a .php filename in the _wp_attached_file metadata field; and then sending this file's content, along with its post_ID value, to (1) wp-app.php or (2) app.php.

Unrestricted file upload vulnerability in (1) wp-app.php and (2) app.php in WordPress 2.2.1 and WordPress MU 1.2.3 allows remote authenticated users to upload and execute arbitrary PHP code via unspecified vectors, possibly related to the wp_postmeta table and the use of custom fields in normal (non-attachment) posts. NOTE: this issue reportedly exists because of an incomplete fix for CVE-2007-3543.

SQL injection vulnerability in wp-admin/admin-ajax.php in WordPress before 2.2 allows remote attackers to execute arbitrary SQL commands via the cookie parameter.

xmlrpc (xmlrpc.php) in WordPress 2.1.2, and probably earlier, allows remote authenticated users with the contributor role to bypass intended access restrictions and invoke the publish_posts functionality, which can be used to "publish a previously saved post."

Cross-site scripting (XSS) vulnerability in wp-includes/general-template.php in WordPress before 20070309 allows remote attackers to inject arbitrary web script or HTML via the year parameter in the wp_title function.

SQL injection vulnerability in xmlrpc (xmlrpc.php) in WordPress 2.1.2, and probably earlier, allows remote authenticated users to execute arbitrary SQL commands via a string parameter value in an XML RPC mt.setPostCategories method call, related to the post_id variable.

Cross-site scripting (XSS) vulnerability in wp-admin/vars.php in WordPress before 2.0.10 RC2, and before 2.1.3 RC2 in the 2.1 series, allows remote authenticated users with theme privileges to inject arbitrary web script or HTML via the PATH_INFO in the administration interface, related to loose regular expression processing of PHP_SELF.

WordPress allows remote attackers to obtain sensitive information via a direct request for wp-admin/admin-functions.php, which reveals the path in an error message.

Cross-site request forgery (CSRF) vulnerability in the AdminPanel in WordPress 2.1.1 and earlier allows remote attackers to perform privileged actions as administrators, as demonstrated using the delete action in wp-admin/post.php. NOTE: this issue can be leveraged to perform cross-site scripting (XSS) attacks and steal cookies via the post parameter.

Cross-site scripting (XSS) vulnerability in the wp_explain_nonce function in the nonce AYS functionality (wp-includes/functions.php) for WordPress 2.0 before 2.0.9 and 2.1 before 2.1.1 allows remote attackers to inject arbitrary web script or HTML via the file parameter to wp-admin/templates.php, and possibly other vectors involving the action variable.

WordPress 2.0.6, and 2.1Alpha 3 (SVN:4662), does not properly verify that the m parameter value has the string data type, which allows remote attackers to obtain sensitive information via an invalid m[] parameter, as demonstrated by obtaining the path, and obtaining certain SQL information such as the table prefix.

wp-trackback.php in WordPress 2.0.6 and earlier does not properly unset variables when the input data includes a numeric parameter with a value matching an alphanumeric parameter's hash value, which allows remote attackers to execute arbitrary SQL commands via the tb_id parameter. NOTE: it could be argued that this vulnerability is due to a bug in the unset PHP command (CVE-2006-3017) and the proper fix should be in PHP; if so, then this should not be treated as a vulnerability in WordPress.