CVE-2026-108554
Description
A flaw was found in pdf2zh. This vulnerability allows an unauthenticated remote attacker to conduct Server-Side Request Forgery (SSRF), where an application is manipulated into sending unauthorized requests to unintended destinations. By submitting a crafted URL that lacks scheme or address validation, an attacker can force the server to access internal network services and cloud metadata endpoints, leading to sensitive information disclosure.
Statement
This vulnerability is rated as Moderate impact because, while unauthenticated remote actors can initiate requests to internal endpoints, the blast radius is confined to sensitive data exposure without system compromise or denial of service. The pdf2zh component is not shipped or supported across Red Hat enterprise products, leaving default installations unexposed.
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.
Frequently Asked Questions
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