An RPM package is a Linux software package format used to distribute and install applications, libraries, and updates on systems that use the RPM ecosystem, such as many Red Hat-based distributions. It bundles the files to install, plus metadata such as version, dependencies, and installation scripts, so package managers can verify what should be present and place it in the right locations.
In cyber security, RPM packages matter because they are part of the trusted software supply chain. Administrators and users rely on signatures and checksums to confirm that a package really came from the expected publisher and was not modified in transit. Attackers may try to replace a legitimate RPM with a trojanized build, while defenders use signing keys, repository controls, and package verification to detect tampering. When release-signing material is exposed or mishandled, trust in RPM downloads can be weakened even if the package files themselves were never changed.