An RCE (remote code execution) exploit is an attack that takes advantage of a vulnerability to run arbitrary code or commands on a target system from a remote location, without physical access and, in many cases, without valid credentials. Once successful, the attacker can typically execute code with the privileges of the vulnerable application or service, which may allow them to install malware or ransomware, steal data, establish persistent access, or move laterally to other systems. Common causes include injection flaws, insecure deserialization, memory corruption bugs such as buffer overflows, and unsafe handling of file uploads or user input.
RCE vulnerabilities are generally rated among the most severe, often scoring critical under CVSS, because they can give an attacker significant control over a system in a single step. Internet-facing RCE vulnerabilities are frequently weaponized within days of disclosure, so their exploitability and exposure warrant urgent attention. When an immediate patch is not possible, compensating controls such as network isolation, web application firewall rules, or disabling the affected feature can reduce risk until the fix is applied.