Aug 2026: Microsoft UFO: IPv6 transition address bypass of SSRF guard in URL validation
CVE-2026-73297 Published on August 12, 2026
Microsoft UFO: IPv6 transition address bypass of SSRF guard in URL validation
Microsoft UFO open-source framework for intelligent automation across devices and platforms. Prior to 3.0.8, _is_blocked_ip in ufo/utils/url_security.py did not block NAT64 prefixes 64:ff9b::/96 and 64:ff9b:1::/48, the 6to4 prefix 2002::/16, or the Teredo prefix 2001::/32 and did not re-check embedded IPv4 destinations, allowing an unauthenticated remote attacker who can influence URLs processed by validate_url to bypass the SSRF guard and reach cloud metadata, internal services, or localhost. This issue is fixed in version 3.0.8.
Vulnerability Analysis
CVE-2026-73297 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. Public availability of a proof of concept (POC) exploit exists for CVE-2026-73297. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity and availability.
Weakness Type
What is a SSRF Vulnerability?
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. 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.
CVE-2026-73297 has been classified to as a SSRF vulnerability or weakness.