CVE-2026-44364

The html_to_markdown expansion module in MISP Modules contains a server-side request forgery (SSRF) vulnerability in its is_safe_url() URL validation function. The BLOCKED_RANGES list was incomplete and omitted 0.0.0.0/8, 100.64.0.0/10, ::/128, fc00::/7, and fe80::/10, as well as IPv4-mapped IPv6 forms, allowing an authenticated user to direct requests to internal addresses from the MISP server's network context.

The cisco_firesight_manager_ACL_rule_export module in misp-modules generates a shell script (.sh) that authenticates to and calls the Cisco fireSIGHT Manager API. The module interpolates configuration values (IP address, login, password, domain ID, policy ID) and MISP attribute values (destination IPs, URLs, event info comments) directly into single-quoted shell string assignments without any escaping or sanitization. Because the values are placed inside single-quoted shell strings, any value containing a single-quote character breaks out of the quoting context, allowing an attacker to inject arbitrary shell commands into the exported script. A security analyst who executes the generated .sh file unmodified would run the injected commands with their own privileges, potentially exposing fireSIGHT Manager credentials, modifying ACL rules, or compromising the analyst workstation. Additionally, the module contained a secondary defect where the variable 'config' was only assigned inside a conditional block but referenced unconditionally afterward, causing a NameError (denial of service) when the request payload lacked a 'config' key.

A Server-Side Request Forgery (SSRF) protection bypass was found in the html_to_markdown expansion module of misp-modules. IPv4-mapped IPv6 addresses were not normalized before blocked-range checks, allowing attacks on loopback, internal, or link-local networks.

MISP modules are autonomous modules that can be used to extend MISP for new services. Prior to 3.0.7, an unsafe remote resource fetching vulnerability existed in MISP Modules expansion modules. The html_to_markdown module accepted arbitrary HTTP(S) URLs without sufficient validation, which could allow Server-Side Request Forgery against loopback, private, or link-local network resources. Additionally, the qrcode module disabled TLS certificate verification when retrieving remote images, exposing requests to potential man-in-the-middle interception or response tampering.