An obsolete IC is an integrated circuit that is no longer commonly manufactured or sold. In practice, that means a device may still work electrically, but maintenance becomes difficult because replacements are scarce, expensive, or only available from salvaged parts. This matters in cybersecurity because old hardware often stays in service inside industrial systems, lab equipment, medical devices, and other long-lived platforms that may also rely on outdated software and weak protections.
Obsolete ICs create a security and reliability problem at the same time. If a critical chip fails, organizations may be forced to keep vulnerable equipment running longer than planned, delay patching, or use unverified replacements. Attackers can benefit from that aging environment, especially where documentation is poor and security updates are rare. Defenders respond by tracking component lifecycles, keeping spare stock, validating replacement parts, and planning migrations before a single unavailable chip becomes a single point of failure.