CRITICAL9.8

GO-2024-2887

Unexpected behavior from Is methods for IPv4-mapped IPv6 addresses in net/netip

Quick fix

GO-2024-2887 — stdlib: upgrade to the fixed version with the command below.

go get stdlib@v1.21.11

Details

The various Is methods (IsPrivate, IsLoopback, etc) did not work as expected for IPv4-mapped IPv6 addresses, returning false for addresses which would return true in their traditional IPv4 forms.

Are you affected?

Enter the version of the package you're using.

Affected packages

Go/stdlib

Introduced in: 0Fixed in: 1.21.11

Fixgo get stdlib@v1.21.11

References

https://go.dev/cl/590316[FIX]
https://go.dev/issue/67680[REPORT]
https://groups.google.com/g/golang-announce/c/XbxouI9gY7k/m/TuoGEhxIEwAJ[WEB]