There is an Open Redirect vulnerability in Gnuboard v6.0.4 and below via the `url` parameter in login path.

Gnuboard g6 6.0.7 is vulnerable to Session hijacking due to a CORS misconfiguration.

Cross Site Scripting (XSS) vulnerability in Gnuboard g6 before Github commit 58c737a263ac0c523592fd87ff71b9e3c07d7cf5, allows remote attackers execute arbitrary code via the wr_content parameter.

** UNSUPPORTED WHEN ASSIGNED ** A vulnerability classified as problematic has been found in gnuboard youngcart5 up to 5.4.5.1. Affected is an unknown function of the file adm/menu_list_update.php. The manipulation of the argument me_link leads to cross site scripting. It is possible to launch the attack remotely. Upgrading to version 5.4.5.2 is able to address this issue. The name of the patch is 70daa537adfa47b87af12d85f1e698fff01785ff. It is recommended to upgrade the affected component. VDB-216954 is the identifier assigned to this vulnerability. NOTE: This vulnerability only affects products that are no longer supported by the maintainer.

Use of a Broken or Risky Cryptographic Algorithm in GitHub repository gnuboard/gnuboard5 prior to and including 5.5.5. A vulnerability in gnuboard v5.5.5 and below uses weak encryption algorithms leading to sensitive information exposure. This allows an attacker to derive the email address of any user, including when the 'Let others see my information.' box is ticked off. Or to send emails to any email address, with full control of its contents

gnuboard5 is vulnerable to Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')