CS0-004: CompTIA Cybersecurity Analyst (CySA+)

Legacy and proprietary systems often cannot be patched without risking system instability or loss of vendor support, and many organizations retain such systems because replacing them is costly or operationally disruptive. In addition, patches for identified vulnerabilities may simply not yet be available from the vendor, and organizations are frequently dependent on third-party vendors to develop, test, and release fixes or to authorize changes before remediation can occur. These factors—legacy/proprietary technology, lack of available patches, and vendor dependency—are the most common real-world reasons that critical vulnerabilities identified during a scan cannot be remediated immediately, as outlined in CompTIA CySA+ vulnerability management guidance.