Claude Code Sandbox Now Fails Closed on Ambiguous Network Rules and Brackets IPv6 Literals
Claude Code Changelog·medium signal
2.1.229 hardened the sandbox network allowlist: IPv6 literals in domain lists are now bracketed (`[::1]:443`), and ambiguous spellings are enforced fail-closed and flagged by `/doctor`. Previously an ambiguously-written entry could be parsed permissively, silently widening what a sandboxed agent could reach. Run `/doctor` after upgrading — entries that used to pass may now surface as warnings.