man > HARDENING-CHECK(1)

HARDENING-CHECK(1)                                                                HARDENING-CHECK(1)

NAME
       hardening-check - check binaries for security hardening features

SYNOPSIS
       hardening-check [options] [ELF ...]

       Examine a given set of ELF binaries and check for several security hardening features,
       failing if they are not all found.

DESCRIPTION
       This utility checks a given list of ELF binaries for several security hardening features that
       can be compiled into an executable. These features are:

       Position Independent Executable
               This  indicates  that  the  executable  was built in such a way (PIE) that the "text"
               section of the program can be relocated in memory. To take  full  advantage  of  this
               feature,  the  executing  kernel must support text Address Space Layout Randomization
               (ASLR).

       Stack Protected
               This indicates that there is evidence that the  ELF  was  compiled  with  the  gcc(1)
               option  -fstack-protector (e.g. uses __stack_chk_fail). The program will be resistant
               to having its stack overflowed.

               When an executable was built without any character  arrays  being  allocated  on  the
               stack,   this   check   will  lead  to  false  alarms  (since  there  is  no  use  of
               __stack_chk_fail), even though it was compiled with the correct options.

       Fortify Source functions
               This indicates that the executable was compiled with -D_FORTIFY_SOURCE=2 and  -O1  or
               higher.  This  causes  certain  unsafe  glibc functions with their safer counterparts
               (e.g. strncpy instead of strcpy), or replaces calls that are  verifiable  at  runtime
               with the runtime-check version (e.g. __memcpy_chk insteade of memcpy).

               When  an executable was built such that the fortified versions of the glibc functions
               are not useful (e.g. use is verified as safe  at  compile  time,  or  use  cannot  be
               verified at runtime), this check will lead to false alarms.  In an effort to mitigate
               this,  the  check will pass if any fortified function is found, and will fail if only
               unfortified functions are found. Uncheckable conditions also pass (e.g. no  functions
               that could be fortified are found, or not linked against glibc).

       Read-only relocations
               This  indicates  that the executable was build with -Wl,-z,relro to have ELF markings
               (RELRO) that ask the runtime linker to mark any regions of the  relocation  table  as
               "read-only"  if they were resolved before execution begins. This reduces the possible
               areas of memory in a program that  can  be  used  by  an  attacker  that  performs  a
               successful memory corruption exploit.

       Immediate binding
               This  indicates  that  the  executable was built with -Wl,-z,now to have ELF markings
               (BIND_NOW) that ask the runtime linker to resolve  all  relocations  before  starting
               program  execution.  When combined with RELRO above, this further reduces the regions
               of memory available to memory corruption attacks.

OPTIONS
       --nopie, -p
               Do not require that the checked binaries be built as PIE.

       --nostackprotector, -s
               Do not require that the checked binaries be built with the stack protector.

       --nofortify, -f
               Do not require that the checked binaries be built with Fortify Source.

       --norelro, -r
               Do not require that the checked binaries be built with RELRO.

       --nobindnow, -b
               Do not require that the checked binaries be built with BIND_NOW.

       --nocfprotection, -b
               Do not require that the checked binaries be built with control flow protection.

       --quiet, -q
               Only report failures.

       --verbose, -v
               Report verbosely on failures.

       --report-functions, -R
               After the report, display all external functions needed by the ELF.

       --find-libc-functions, -F
               Instead of the regular report, locate the libc for the first ELF on the command  line
               and report all the known "fortified" functions exported by libc.

       --color, -c
               Enable colorized status output.

       --lintian, -l
               Switch reporting to lintian-check-parsable output.

       --debug Report some debugging during processing.

       --help, -h, -?
               Print a brief help message and exit.

       --man, -H
               Print the manual page and exit.

RETURN VALUE
       When  all  checked binaries have all checkable hardening features detected, this program will
       finish with an exit code of 0. If any check fails, the exit code with be 1. Individual checks
       can be disabled via command line options.

AUTHOR
       Kees Cook <kees AT debian.org>

COPYRIGHT AND LICENSE
       Copyright 2009-2013 Kees Cook <kees AT debian.org>.

       This program is free software; you can redistribute it and/or modify it under  the  terms  of
       the  GNU  General  Public  License as published by the Free Software Foundation; version 2 or
       later.

SEE ALSO
       gcc(1), hardening-wrapper(1)

Debian Utilities                             2026-02-25                           HARDENING-CHECK(1)