Linux's Security Capabilities

2.4 Setting capabilities to processes

• Use the execcap utility to start a process with a limited set of capabilities:
  • execcap <caps> <command-path> command-args...
    • Will execute a tamagoshi server on priviliged port 999.

    • Process runs as root but can only use priviliged ports

    • If a vulnerability appears in the server, it could be used to gain access to files owned by root.

• Use the sucap utility to start a process with a limited set of capabilities and to specify the user and group ID the program should execute as:
  • sucap <user> <group> <caps> <command-path> command-args...
    • Will execute a tamagoshi server as user tama of group tama but has capability to open priviliges port

    • If a vulnerability appears in the server, it will only enable access to files owned by tama

    • Caution: In some cases the file will start executing itself without having it's capabilities granted. This will disapear as soon as capabilities will be managed at the file level.

Linux's Security Capabilities

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