suid_dumpable

file: /proc/sys/fs/suid_dumpable
variable: fs.suid_dumpable
Official reference

This value can be used to query and set the core dump mode for setuid or otherwise protected/tainted binaries. The modes are

  1. (default) - traditional behaviour. Any process which has changed privilege levels or is execute only will not be dumped.
  2. (debug) - all processes dump core when possible. The core dump is owned by the current user and no security is applied. This is intended for system debugging situations only. Ptrace is unchecked. This is insecure as it allows regular users to examine the memory contents of privileged processes.
  3. (suidsafe) - any binary which normally would not be dumped is dumped anyway, but only if the “core_pattern” kernel sysctl is set to either a pipe handler or a fully qualified path. (For more details on this limitation, see CVE-2006-2451.) This mode is appropriate when administrators are attempting to debug problems in a normal environment, and either have a core dump pipe handler that knows to treat privileged core dumps with care, or specific directory defined for catching core dumps. If a core dump happens without a pipe handler or fully qualifid path, a message will be emitted to syslog warning about the lack of a correct setting.
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