CVE-2026-62993
Description
A flaw was found in Smarty, a PHP template engine. The {fetch} function, when a security policy was active, only validated the initial remote URL against a trusted_uri allowlist. However, PHP's file_get_contents() function, used for resources including HTTPS URLs, followed HTTP redirects by default. This allowed an attacker to supply or influence a fetch target with an open redirect on a trusted host, redirecting the request to an attacker-chosen internal endpoint. This bypasses the trusted_uri allowlist and enables Server-Side Request Forgery (SSRF).
Statement
Red Hat Product Security has determined that this vulnerability does not affect any currently supported Red Hat product. This assessment may evolve based on further analysis and discovery. For more information about this vulnerability and the products it affects, please see the linked references.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Application Data
Integrity
Technical Impact: Execute Unauthorized Code or Commands
Access Control
Technical Impact: Bypass Protection Mechanism
By providing URLs to unexpected hosts or ports, attackers can make it appear that the server is sending the request, possibly bypassing access controls such as firewalls that prevent the attackers from accessing the URLs directly. The server can be used as a proxy to conduct port scanning of hosts in internal networks, use other URLs such as that can access documents on the system (using file://), or use other protocols such as gopher:// or tftp://, which may provide greater control over the contents of requests.
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