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."

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 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.

The wp_remote_fopen function in WordPress before 2.1 allows remote attackers to cause a denial of service (bandwidth or thread consumption) via pingback service calls with a source URI that corresponds to a large file, which triggers a long download session without a timeout constraint.

WordPress allows remote attackers to cause a denial of service (bandwidth or thread consumption) via pingback service calls with a source URI that corresponds to a file with a binary content type, which is downloaded even though it cannot contain usable pingback data.

WordPress allows remote attackers to determine the existence of arbitrary files, and possibly read portions of certain files, via pingback service calls with a source URI that corresponds to a local pathname, which triggers different fault codes for existing and non-existing files, and in certain configurations causes a brief file excerpt to be published as a blog comment.

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.

WordPress before 2.0.6, when mbstring is enabled for PHP, decodes alternate character sets after escaping the SQL query, which allows remote attackers to bypass SQL injection protection schemes and execute arbitrary SQL commands via multibyte charsets, as demonstrated using UTF-7.

Cross-site scripting (XSS) vulnerability in wp-admin/templates.php in WordPress 2.0.5 allows remote attackers to inject arbitrary web script or HTML via the file parameter. NOTE: some sources have reported this as a vulnerability in the get_file_description function in wp-admin/admin-functions.php.

wp-admin/user-edit.php in WordPress before 2.0.5 allows remote authenticated users to read the metadata of an arbitrary user via a modified user_id parameter.

WordPress before 2.0.5 does not properly store a profile containing a string representation of a serialized object, which allows remote authenticated users to cause a denial of service (application crash) via a string that represents a (1) malformed or (2) large serialized object, because the object triggers automatic unserialization for display.

Multiple directory traversal vulnerabilities in plugins/wp-db-backup.php in WordPress before 2.0.5 allow remote authenticated users to read or overwrite arbitrary files via directory traversal sequences in the (1) backup and (2) fragment parameters in a GET request.