CVE-2025-22870: HTTP Proxy bypass using IPv6 Zone IDs in golang.org/x/net
Matching of hosts against proxy patterns can improperly treat an IPv6 zone ID as a hostname component. For example, when the NO_PROXY environment variable is set to "*.example.com", a request to "[::1%25.example.com]:80` will incorrectly match and not be proxied.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2025-22870?
CVE-2025-22870 is classified as a moderate severity vulnerability due to improper handling of IPv6 zone IDs in proxy pattern matching.
How do I fix CVE-2025-22870?
To fix CVE-2025-22870, update to the latest version of the golang.org/x/net package where the issue has been addressed.
What types of systems are affected by CVE-2025-22870?
CVE-2025-22870 affects systems using the Golang library, specifically those making use of proxy settings with IPv6 addresses.
What kind of attacks can occur due to CVE-2025-22870?
Exploitation of CVE-2025-22870 could lead to sensitive information being leaked or improper access control in applications that rely on proxy configurations.
Is it safe to use the NO_PROXY environment variable with CVE-2025-22870?
Using the NO_PROXY environment variable in environments affected by CVE-2025-22870 can lead to unintended behavior, making it unsafe until the vulnerability is mitigated.