CVE-2026-62143
HighCVSS 8.3Exploitation Probability (EPSS)
Low risk34th percentile - higher than 34% of all known CVEs
Summary
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.
Risk Assessment
An attacker could access internal HTTP services, administrative interfaces, or cloud instance metadata, with retrieved content potentially returned as converted Markdown, leading to sensitive information disclosure.
Recommendation
Immediately update misp-modules to a version that normalizes IPv4-mapped IPv6 addresses and rejects URLs without a valid hostname.
Other vulnerabilities in misp-modules
See all- CVE-2026-44364Critical
In versions 3.0.7 and earlier, there is a Cross-Site Request Forgery (CSRF) vulnerability in MISP Modules that allows an attacker to cause an authenticated user to submit unintended requests to the home endpoint. The issue was due to the home blueprint being exempted from CSRF protection.
- CVE-2026-112991Medium
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.
- CVE-2026-97863Medium
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.
- CVE-2026-44363Medium
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.
Original NVD description (English source)
A Server-Side Request Forgery (SSRF) protection bypass existed in the html_to_markdown expansion module of misp-modules. The module attempts to prevent requests to loopback, private, link-local, and other restricted IP address ranges. However, IP addresses were compared against the blocked ranges without first normalising IPv4-mapped IPv6 addresses. An authenticated attacker able to invoke the module could supply an IPv4-mapped IPv6 address, such as: http://[::ffff:127.0.0.1]/ http://[::ffff:169.254.169.254]/ Alternatively, the attacker could use a hostname that resolves to an IPv4-mapped IPv6 address. These addresses were treated as IPv6 addresses and therefore did not match the corresponding blocked IPv4 ranges. Successful exploitation could cause the misp-modules server to connect to services available through its loopback interface, internal network, or link-local network. This could expose internal web services, administrative interfaces, or cloud instance metadata, with retrieved content potentially returned to the attacker as converted Markdown. The vulnerability has been addressed by normalising IPv4-mapped IPv6 addresses to their underlying IPv4 representation before applying the blocked-range checks. URLs without a valid hostname are now also rejected.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

