# CVE-2026-54390

> JTL Shop versions 5.2.0 through 5.7.1 contains a server-side template injection vulnerability that allows unauthenticated attackers to inject malicious template syntax due to unsanitized user-supplied input passed to the Smarty template engine. Attackers can exploit this flaw to read sensitive server-side values such as database credentials and encryption keys, and on versions 5.4.0 through 5.7.1, leverage registered Smarty modifiers including unserialize and file_get_contents to write a webshell to the web root and execute arbitrary commands as the web server user.

- **CVSS:** 9.8 (CRITICAL)
- **CWE:** CWE-1336

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-54390
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