Resource limits are caps on how much memory, disk space, file size, CPU time, or runtime a process may use. In security-sensitive file handling, they keep parsers and converters from working on untrusted input indefinitely or at unsafe scale. This matters because a crafted upload can be designed to expand, recurse, or trigger expensive processing, turning a simple file operation into a denial-of-service risk or a wider abuse path.
In real defenses, resource limits are applied to image processors, document converters, and upload workers. Administrators may enforce timeouts, maximum dimensions, size quotas, and container or OS-level quotas so a malicious file cannot exhaust server resources or probe too much of the host. Limits do not fix a parsing flaw by themselves, but they reduce the blast radius when a bug exists and make file-processing pipelines safer to expose on the internet.