Bash Permission Checks Were Auto-Approving Arithmetic Assignments Like OPTIND=1/0
Claude Code Changelog·medium signal
2.1.251 fixes Bash permission checks auto-approving commands that assign an arithmetic expression to an integer shell variable, naming `OPTIND=1/0` and `RANDOM=2+2` as examples; these now prompt for approval. The same release also changes how Bash command output files are created and read back in the sandbox so a sandboxed command cannot redirect or replace them. Both are parser-level gaps where the shape of a command, not its effect, decided whether it needed approval.