CVE-2026-42449 n8n-MCP: IPv4-mapped IPv6 addresses bypass SSRF protection in validateUrlSync(), enabling full SSRF for SDK embedders

n8n-MCP is an MCP server that provides AI assistants access to n8n node documentation, properties, and operations. In versions 2.47.4 through 2.47.13, the SDK embedder path N8NDocumentationMCPServer constructor, getN8nApiClient, and validateInstanceContext, the synchronous URL validator in...

CVE-2026-42449

Summary: CVE-2026-42449 affects n8n-mcp SDK embedder paths where SSRF protection (SSRFProtection.validateUrlSync) fails to validate IPv4-mapped IPv6 addresses, enabling an attacker-controlled n8nApiUrl to cause the server to make HTTP requests to internal networks, cloud metadata endpoints, or lo...

Updated perl-Net-CIDR-Lite packages fix security vulnerabilities

Net::CIDR::Lite versions before 0.23 for Perl does not validate IPv6 group count, which may allow IP ACL bypass. CVE-2026-40198 Net::CIDR::Lite versions before 0.23 for Perl mishandles IPv4 mapped IPv6 addresses, which may allow IP ACL bypass. CVE-2026-40199...

CVE-2026-33975

Twenty is an open source CRM built with NestJS Node.js. In versions 1.18.0 and earlier, the SSRF protection in twenty-server's SecureHttpClientService can be bypassed using IPv4-mapped IPv6 addresses in URL IP literals. Node.js's URL parser normalizes IPv4-mapped IPv6 addresses to compressed hex...

Server-side Request Forgery (SSRF)

Overview Affected versions of this package are vulnerable to Server-side Request Forgery SSRF in the isSSRFSafeURL function. An attacker can access internal network resources and sensitive cloud metadata by submitting specially crafted URLs that use IPv4-mapped IPv6 notation, which bypasses the...

GHSA-J4RJ-2JR5-M439 ssrfcheck Vulnerable to Server-Side Request Forgery (SSRF) and Incomplete List of Disallowed Inputs

Summary ssrfcheck v1.3.0 latest fails to block Server-Side Request Forgery attacks when the target private IP address is encoded as an IPv4-mapped IPv6 address e.g. http://::ffff:127.0.0.1/. The WHATWG URL parser built into Node.js silently normalizes the IPv4 notation inside the brackets to...

CVE-2026-33975 twenty-server SSRF protection bypass via IPv4-mapped IPv6 address normalization

Twenty is an open source CRM built with NestJS Node.js. In versions 1.18.0 and earlier, the SSRF protection in twenty-server's SecureHttpClientService can be bypassed using IPv4-mapped IPv6 addresses in URL IP literals. Node.js's URL parser normalizes IPv4-mapped IPv6 addresses to compressed hex...

CVE-2026-33975 twenty-server SSRF protection bypass via IPv4-mapped IPv6 address normalization

Twenty is an open source CRM built with NestJS Node.js. In versions 1.18.0 and earlier, the SSRF protection in twenty-server's SecureHttpClientService can be bypassed using IPv4-mapped IPv6 addresses in URL IP literals. Node.js's URL parser normalizes IPv4-mapped IPv6 addresses to compressed hex...

PT-2026-37306

Name of the Vulnerable Software and Affected Versions ssrfcheck versions 1.3.0 and earlier Description ssrfcheck fails to block Server-Side Request Forgery SSRF attacks when a target private IP address is encoded as an IPv4-mapped IPv6 address e.g., 'http://::ffff:127.0.0.1/'. This occurs because...

PT-2026-37221

Twenty is an open source CRM built with NestJS Node.js. In versions 1.18.0 and earlier, the SSRF protection in twenty-server's SecureHttpClientService can be bypassed using IPv4-mapped IPv6 addresses in URL IP literals. Node.js's URL parser normalizes IPv4-mapped IPv6 addresses to compressed hex...

RHCOS 4 : OpenShift Container Platform 4.15.28 (RHSA-2024:5442)

The remote Red Hat Enterprise Linux CoreOS 4 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2024:5442 advisory. - golang: net/http: golang: mime/multipart: golang: net/textproto: memory exhaustion in Request.ParseMultipartForm CVE-2023-45290 -...

n8n-mcp's IPv4-mapped IPv6 addresses bypass SSRF protection in validateUrlSync(), enabling full SSRF for SDK embedders

Impact In the SDK embedder path N8NDocumentationMCPServer constructor, getN8nApiClient, and validateInstanceContext, the synchronous URL validator in SSRFProtection.validateUrlSync had no IPv6 checks. IPv4-mapped IPv6 addresses such as http://::ffff:169.254.169.254 bypassed the cloud-metadata,...

Medium: perl-Net-CIDR-Lite

Issue Overview: Net::CIDR::Lite versions before 0.23 for Perl does not validate IPv6 group count, which may allow IP ACL bypass. packipv6 does not check that uncompressed IPv6 addresses without :: have exactly 8 hex groups. Inputs like "abcd", "1:2:3", or "1:2:3:4:5:6:7" are accepted and produce...

PT-2026-36822

Name of the Vulnerable Software and Affected Versions n8n-MCP versions 2.47.4 through 2.47.13 Description The synchronous URL validator in SSRFProtection.validateUrlSync lacks IPv6 checks within the SDK embedder path, specifically affecting the N8NDocumentationMCPServer constructor,...

CVE-2026-31630

In the Linux kernel, the following vulnerability has been resolved: rxrpc: proc: size address buffers for %pISpc output The AFRXRPC procfs helpers format local and remote socket addresses into fixed 50-byte stack buffers with "%pISpc". That is too small for the longest current-tree IPv6-with-port...

Fedora 42 : perl-Net-CIDR-Lite (2026-4b112416d8)

The remote Fedora 42 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-4b112416d8 advisory. This update addresses two security issues regarding incorrect handling of malformed IPv6 addresses: Fix IPv4 mapped IPv6 packed length CVE-2026-4019...

PT-2026-41172

Name of the Vulnerable Software and Affected Versions Open WebUI versions prior to 0.9.0 Description A Server-Side Request Forgery SSRF bypass exists in the validate url function located in backend/open webui/retrieval/web/utils.py. The function calls validators.ipv6ip, private=True, but because...

CVE-2026-40199

Net::CIDR::Lite versions before 0.23 for Perl mishandles IPv4 mapped IPv6 addresses, which may allow IP ACL bypass. packipv6 includes the sentinel byte from packipv4 when building the packed representation of IPv4 mapped addresses like ::ffff:192.168.1.1. This produces an 18 byte value instead of...

EUVD-2026-21611

Net::CIDR::Lite versions before 0.23 for Perl mishandles IPv4 mapped IPv6 addresses, which may allow IP ACL bypass. packipv6 includes the sentinel byte from packipv4 when building the packed representation of IPv4 mapped addresses like ::ffff:192.168.1.1. This produces an 18 byte value instead of...

DEBIAN-CVE-2026-40199

Net::CIDR::Lite versions before 0.23 for Perl mishandles IPv4 mapped IPv6 addresses, which may allow IP ACL bypass. packipv6 includes the sentinel byte from packipv4 when building the packed representation of IPv4 mapped addresses like ::ffff:192.168.1.1. This produces an 18 byte value instead of...