Incomplete blacklist vulnerability in mainfile.php in PHP-Nuke 7.9 and earlier allows remote attackers to conduct SQL injection attacks via (1) "/**/UNION " or (2) " UNION/**/" sequences, which are not rejected by the protection mechanism, as demonstrated by a SQL injection via the eid parameter in a search action in the Encyclopedia module in modules.php.

Cross-site scripting (XSS) vulnerability in the Your_Account module in PHP-Nuke 7.8 might allows remote attackers to inject arbitrary HTML and web script via the ublock parameter, which is saved in the user's personal menu. NOTE: the provenance of this information is unknown; the details are obtained solely from third party information. In addition, it is unclear whether this issue is a vulnerability, since it is related to the user's personal menu, which presumably is not modifiable by others.

SQL injection vulnerability in the Your_Account module in PHP-Nuke 7.8 might allows remote attackers to execute arbitrary SQL commands via the user_id parameter in the Your_Home functionality. NOTE: the provenance of this information is unknown; the details are obtained solely from third party information.

SQL injection vulnerability in PHP-Nuke before 7.8 Patched 3.2 allows remote attackers to execute arbitrary SQL commands via encoded /%2a (/*) sequences in the query string, which bypasses regular expressions that are intended to protect against SQL injection, as demonstrated via the kala parameter.

PHP-Nuke 7.8 Patched 3.2 allows remote attackers to bypass SQL injection protection mechanisms via /%2a (/*) sequences with the "ad_click" word in the query string, as demonstrated via the kala parameter.

The CAPTCHA functionality in php-Nuke 6.0 through 7.9 uses fixed challenge/response pairs that only vary once per day based on the User Agent (HTTP_USER_AGENT), which allows remote attackers to bypass CAPTCHA controls by fixing the User Agent, performing a valid challenge/response, then replaying that pair in the random_num and gfx_check parameters.

SQL injection vulnerability in index.php in the Your_Account module in PHP-Nuke 7.8 and earlier allows remote attackers to execute arbitrary SQL commands via the username variable (Nickname field).

Cross-site scripting (XSS) vulnerability in header.php in PHP-Nuke 6.0 to 7.8 allows remote attackers to inject arbitrary web script or HTML via the pagetitle parameter.

Multiple SQL injection vulnerabilities in modules.php in PHP-Nuke 7.8, when magic_quotes_gpc is disabled, allow remote attackers to execute arbitrary SQL commands via the (1) name, (2) sid, and (3) pid parameters in a POST request, which bypasses security checks that are performed for GET requests.

Interpretation conflict in includes/mainfile.php in PHP-Nuke 7.9 and later allows remote attackers to perform cross-site scripting (XSS) attacks by replacing the ">" in the tag with a "<", which bypasses the regular expressions that sanitize the data, but is automatically corrected by many web browsers. NOTE: it could be argued that this vulnerability is due to a design limitation of many web browsers; if so, then this should not be treated as a vulnerability in PHP-Nuke.