299Ko Contact Form Plugin Template Engine common/Template.php _show_var name/firstname/email/message cross site scripting

Summaryinfo

A vulnerability, which was classified as problematic, has been found in 299Ko Contact Form Plugin. Affected by this vulnerability is the function _show_var of the file common/Template.php of the component Template Engine. The manipulation of the argument name/firstname/email/message leads to cross site scripting. This vulnerability is uniquely identified as CVE-2026-71249. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in 299Ko Contact Form Plugin (affected version unknown) and classified as problematic. This issue affects the function _show_var of the file common/Template.php of the component Template Engine. The manipulation of the argument name/firstname/email/message with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. The summary by CVE is:

299Ko's public contact form (plugin/contact/controllers/ContactController.php, home()) sets raw POST field values (name, firstname, email, message) into the page template with no sanitization. The template engine's variable output function (common/Template.php, _show_var()) echoes values with no htmlspecialchars() call, and the sink template (contact.tpl) outputs these values unescaped into an HTML attribute and a textarea. An unauthenticated attacker can submit a payload such as name="><script>alert(document.domain)</script> to achieve reflected XSS against any visitor who submits or is tricked into auto-submitting the form, including a targeted administrator, enabling session token theft.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-71249 since 08/05/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

By approaching the search of inurl:common/Template.php it is possible to find vulnerable targets with Google Hacking.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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Vendor

• 299Ko

Name

• Contact Form Plugin

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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