Bug#808316: grub-common: Grub supports running the system even if you forget the password

Himanshu Shekhar himanshushekharb16 at gmail.com
Fri Dec 18 15:28:01 UTC 2015


Package: grub-common
Version: 2.02~beta2-22+deb8u1
Severity: important

Dear Maintainer,

* What led up to the situation?

There are tons of articles available on the internet which detail about the
steps in case you forget the password, you can find one here
(http://www.howtogeek.com/howto/linux/reset-your-forgotten-ubuntu-password-in-2
-minutes-or-less/ ).

Articles like the above, say to add the text "mount -rw -o remount /" to the
kernel line, after pressing e in the grub menu, after which the person having
the physical possession of the system has the root access.

Physical possession is bit difficult in case of servers and desktops, but is
very easy in today's world where laptop users are also loving Linux on their
portable systems.

* What exactly did you do (or not do) that was effective (or ineffective)?

There were concerns on the internet about the bug that gave root access after
pressing backspace 28 times, which was considered threat.
However, I knew this from long and considered this method also as a security
threat.

There should be some way to give the user the method to recover the lost
password in worst cases, but prevent any such unauthorised user with physical
possession of systems gain root access within a minute and mess up everything.



-- Package-specific info:

*********************** BEGIN /proc/mounts
/dev/sda1 / ext3 rw,relatime,errors=remount-ro,data=ordered 0 0
/dev/sda5 /media/himanshu/himanshu fuseblk rw,relatime,user_id=0,group_id=0,allow_other,blksize=4096 0 0
*********************** END /proc/mounts

*********************** BEGIN /boot/grub/grub.cfg
#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#

### BEGIN /etc/grub.d/00_header ###
if [ -s $prefix/grubenv ]; then
  set have_grubenv=true
  load_env
fi
if [ "${next_entry}" ] ; then
   set default="${next_entry}"
   set next_entry=
   save_env next_entry
   set boot_once=true
else
   set default="0"
fi

if [ x"${feature_menuentry_id}" = xy ]; then
  menuentry_id_option="--id"
else
  menuentry_id_option=""
fi

export menuentry_id_option

if [ "${prev_saved_entry}" ]; then
  set saved_entry="${prev_saved_entry}"
  save_env saved_entry
  set prev_saved_entry=
  save_env prev_saved_entry
  set boot_once=true
fi

function savedefault {
  if [ -z "${boot_once}" ]; then
    saved_entry="${chosen}"
    save_env saved_entry
  fi
}
function load_video {
  if [ x$feature_all_video_module = xy ]; then
    insmod all_video
  else
    insmod efi_gop
    insmod efi_uga
    insmod ieee1275_fb
    insmod vbe
    insmod vga
    insmod video_bochs
    insmod video_cirrus
  fi
}

if [ x$feature_default_font_path = xy ] ; then
   font=unicode
else
insmod part_gpt
insmod ext2
set root='hd0,gpt1'
if [ x$feature_platform_search_hint = xy ]; then
  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt1 --hint-efi=hd0,gpt1 --hint-baremetal=ahci0,gpt1  c5c12eeb-c91b-4dc0-9bf0-be761e43af8f
else
  search --no-floppy --fs-uuid --set=root c5c12eeb-c91b-4dc0-9bf0-be761e43af8f
fi
    font="/usr/share/grub/unicode.pf2"
fi

if loadfont $font ; then
  set gfxmode=auto
  load_video
  insmod gfxterm
  set locale_dir=$prefix/locale
  set lang=en_IN
  insmod gettext
fi
terminal_output gfxterm
if [ "${recordfail}" = 1 ] ; then
  set timeout=-1
else
  if [ x$feature_timeout_style = xy ] ; then
    set timeout_style=menu
    set timeout=5
  # Fallback normal timeout code in case the timeout_style feature is
  # unavailable.
  else
    set timeout=5
  fi
fi
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/05_debian_theme ###
insmod part_gpt
insmod ext2
set root='hd0,gpt1'
if [ x$feature_platform_search_hint = xy ]; then
  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt1 --hint-efi=hd0,gpt1 --hint-baremetal=ahci0,gpt1  c5c12eeb-c91b-4dc0-9bf0-be761e43af8f
else
  search --no-floppy --fs-uuid --set=root c5c12eeb-c91b-4dc0-9bf0-be761e43af8f
fi
insmod png
if background_image /usr/share/images/desktop-base/lines-grub.png; then
  set color_normal=white/black
  set color_highlight=black/white
else
  set menu_color_normal=cyan/blue
  set menu_color_highlight=white/blue
fi
### END /etc/grub.d/05_debian_theme ###

### BEGIN /etc/grub.d/10_linux ###
function gfxmode {
	set gfxpayload="${1}"
}
set linux_gfx_mode=
export linux_gfx_mode
menuentry 'Debian GNU/Linux' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-c5c12eeb-c91b-4dc0-9bf0-be761e43af8f' {
	load_video
	insmod gzio
	if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
	insmod part_gpt
	insmod ext2
	set root='hd0,gpt1'
	if [ x$feature_platform_search_hint = xy ]; then
	  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt1 --hint-efi=hd0,gpt1 --hint-baremetal=ahci0,gpt1  c5c12eeb-c91b-4dc0-9bf0-be761e43af8f
	else
	  search --no-floppy --fs-uuid --set=root c5c12eeb-c91b-4dc0-9bf0-be761e43af8f
	fi
	echo	'Loading Linux 3.16.0-4-amd64 ...'
	linux	/boot/vmlinuz-3.16.0-4-amd64 root=UUID=c5c12eeb-c91b-4dc0-9bf0-be761e43af8f ro  quiet
	echo	'Loading initial ramdisk ...'
	initrd	/boot/initrd.img-3.16.0-4-amd64
}
submenu 'Advanced options for Debian GNU/Linux' $menuentry_id_option 'gnulinux-advanced-c5c12eeb-c91b-4dc0-9bf0-be761e43af8f' {
	menuentry 'Debian GNU/Linux, with Linux 3.16.0-4-amd64' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-3.16.0-4-amd64-advanced-c5c12eeb-c91b-4dc0-9bf0-be761e43af8f' {
		load_video
		insmod gzio
		if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
		insmod part_gpt
		insmod ext2
		set root='hd0,gpt1'
		if [ x$feature_platform_search_hint = xy ]; then
		  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt1 --hint-efi=hd0,gpt1 --hint-baremetal=ahci0,gpt1  c5c12eeb-c91b-4dc0-9bf0-be761e43af8f
		else
		  search --no-floppy --fs-uuid --set=root c5c12eeb-c91b-4dc0-9bf0-be761e43af8f
		fi
		echo	'Loading Linux 3.16.0-4-amd64 ...'
		linux	/boot/vmlinuz-3.16.0-4-amd64 root=UUID=c5c12eeb-c91b-4dc0-9bf0-be761e43af8f ro  quiet
		echo	'Loading initial ramdisk ...'
		initrd	/boot/initrd.img-3.16.0-4-amd64
	}
	menuentry 'Debian GNU/Linux, with Linux 3.16.0-4-amd64 (recovery mode)' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-3.16.0-4-amd64-recovery-c5c12eeb-c91b-4dc0-9bf0-be761e43af8f' {
		load_video
		insmod gzio
		if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
		insmod part_gpt
		insmod ext2
		set root='hd0,gpt1'
		if [ x$feature_platform_search_hint = xy ]; then
		  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt1 --hint-efi=hd0,gpt1 --hint-baremetal=ahci0,gpt1  c5c12eeb-c91b-4dc0-9bf0-be761e43af8f
		else
		  search --no-floppy --fs-uuid --set=root c5c12eeb-c91b-4dc0-9bf0-be761e43af8f
		fi
		echo	'Loading Linux 3.16.0-4-amd64 ...'
		linux	/boot/vmlinuz-3.16.0-4-amd64 root=UUID=c5c12eeb-c91b-4dc0-9bf0-be761e43af8f ro single 
		echo	'Loading initial ramdisk ...'
		initrd	/boot/initrd.img-3.16.0-4-amd64
	}
}

### END /etc/grub.d/10_linux ###

### BEGIN /etc/grub.d/20_linux_xen ###

### END /etc/grub.d/20_linux_xen ###

### BEGIN /etc/grub.d/30_os-prober ###
menuentry 'elementary OS Freya (0.3.2) (on /dev/sda3)' --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-simple-150bbed2-e29e-4a96-8f9e-6e993e22df04' {
	insmod part_gpt
	insmod ext2
	set root='hd0,gpt3'
	if [ x$feature_platform_search_hint = xy ]; then
	  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt3 --hint-efi=hd0,gpt3 --hint-baremetal=ahci0,gpt3  150bbed2-e29e-4a96-8f9e-6e993e22df04
	else
	  search --no-floppy --fs-uuid --set=root 150bbed2-e29e-4a96-8f9e-6e993e22df04
	fi
	linux /boot/vmlinuz-3.19.0-39-generic root=UUID=150bbed2-e29e-4a96-8f9e-6e993e22df04 ro quiet splash $vt_handoff
	initrd /boot/initrd.img-3.19.0-39-generic
}
submenu 'Advanced options for elementary OS Freya (0.3.2) (on /dev/sda3)' $menuentry_id_option 'osprober-gnulinux-advanced-150bbed2-e29e-4a96-8f9e-6e993e22df04' {
	menuentry 'elementary OS (on /dev/sda3)' --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-/boot/vmlinuz-3.19.0-39-generic--150bbed2-e29e-4a96-8f9e-6e993e22df04' {
		insmod part_gpt
		insmod ext2
		set root='hd0,gpt3'
		if [ x$feature_platform_search_hint = xy ]; then
		  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt3 --hint-efi=hd0,gpt3 --hint-baremetal=ahci0,gpt3  150bbed2-e29e-4a96-8f9e-6e993e22df04
		else
		  search --no-floppy --fs-uuid --set=root 150bbed2-e29e-4a96-8f9e-6e993e22df04
		fi
		linux /boot/vmlinuz-3.19.0-39-generic root=UUID=150bbed2-e29e-4a96-8f9e-6e993e22df04 ro quiet splash $vt_handoff
		initrd /boot/initrd.img-3.19.0-39-generic
	}
	menuentry 'elementary OS, with Linux 3.19.0-39-generic (on /dev/sda3)' --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-/boot/vmlinuz-3.19.0-39-generic--150bbed2-e29e-4a96-8f9e-6e993e22df04' {
		insmod part_gpt
		insmod ext2
		set root='hd0,gpt3'
		if [ x$feature_platform_search_hint = xy ]; then
		  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt3 --hint-efi=hd0,gpt3 --hint-baremetal=ahci0,gpt3  150bbed2-e29e-4a96-8f9e-6e993e22df04
		else
		  search --no-floppy --fs-uuid --set=root 150bbed2-e29e-4a96-8f9e-6e993e22df04
		fi
		linux /boot/vmlinuz-3.19.0-39-generic root=UUID=150bbed2-e29e-4a96-8f9e-6e993e22df04 ro quiet splash $vt_handoff
		initrd /boot/initrd.img-3.19.0-39-generic
	}
	menuentry 'elementary OS, with Linux 3.19.0-39-generic (recovery mode) (on /dev/sda3)' --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-/boot/vmlinuz-3.19.0-39-generic-root=UUID=150bbed2-e29e-4a96-8f9e-6e993e22df04 ro recovery nomodeset-150bbed2-e29e-4a96-8f9e-6e993e22df04' {
		insmod part_gpt
		insmod ext2
		set root='hd0,gpt3'
		if [ x$feature_platform_search_hint = xy ]; then
		  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt3 --hint-efi=hd0,gpt3 --hint-baremetal=ahci0,gpt3  150bbed2-e29e-4a96-8f9e-6e993e22df04
		else
		  search --no-floppy --fs-uuid --set=root 150bbed2-e29e-4a96-8f9e-6e993e22df04
		fi
		linux /boot/vmlinuz-3.19.0-39-generic root=UUID=150bbed2-e29e-4a96-8f9e-6e993e22df04 ro recovery nomodeset
		initrd /boot/initrd.img-3.19.0-39-generic
	}
	menuentry 'elementary OS, with Linux 3.19.0-33-generic (on /dev/sda3)' --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-/boot/vmlinuz-3.19.0-33-generic--150bbed2-e29e-4a96-8f9e-6e993e22df04' {
		insmod part_gpt
		insmod ext2
		set root='hd0,gpt3'
		if [ x$feature_platform_search_hint = xy ]; then
		  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt3 --hint-efi=hd0,gpt3 --hint-baremetal=ahci0,gpt3  150bbed2-e29e-4a96-8f9e-6e993e22df04
		else
		  search --no-floppy --fs-uuid --set=root 150bbed2-e29e-4a96-8f9e-6e993e22df04
		fi
		linux /boot/vmlinuz-3.19.0-33-generic root=UUID=150bbed2-e29e-4a96-8f9e-6e993e22df04 ro quiet splash $vt_handoff
		initrd /boot/initrd.img-3.19.0-33-generic
	}
	menuentry 'elementary OS, with Linux 3.19.0-33-generic (recovery mode) (on /dev/sda3)' --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-/boot/vmlinuz-3.19.0-33-generic-root=UUID=150bbed2-e29e-4a96-8f9e-6e993e22df04 ro recovery nomodeset-150bbed2-e29e-4a96-8f9e-6e993e22df04' {
		insmod part_gpt
		insmod ext2
		set root='hd0,gpt3'
		if [ x$feature_platform_search_hint = xy ]; then
		  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt3 --hint-efi=hd0,gpt3 --hint-baremetal=ahci0,gpt3  150bbed2-e29e-4a96-8f9e-6e993e22df04
		else
		  search --no-floppy --fs-uuid --set=root 150bbed2-e29e-4a96-8f9e-6e993e22df04
		fi
		linux /boot/vmlinuz-3.19.0-33-generic root=UUID=150bbed2-e29e-4a96-8f9e-6e993e22df04 ro recovery nomodeset
		initrd /boot/initrd.img-3.19.0-33-generic
	}
}

### END /etc/grub.d/30_os-prober ###

### BEGIN /etc/grub.d/30_uefi-firmware ###
### END /etc/grub.d/30_uefi-firmware ###

### BEGIN /etc/grub.d/40_custom ###
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
### END /etc/grub.d/40_custom ###

### BEGIN /etc/grub.d/41_custom ###
if [ -f  ${config_directory}/custom.cfg ]; then
  source ${config_directory}/custom.cfg
elif [ -z "${config_directory}" -a -f  $prefix/custom.cfg ]; then
  source $prefix/custom.cfg;
fi
### END /etc/grub.d/41_custom ###
*********************** END /boot/grub/grub.cfg

*********************** BEGIN /proc/mdstat
cat: /proc/mdstat: No such file or directory
*********************** END /proc/mdstat

*********************** BEGIN /dev/disk/by-id
total 0
lrwxrwxrwx 1 root root  9 Dec 18 20:36 ata-MATSHITA_DVD+_-RW_UJ8E2_H086_017619 -> ../../sr0
lrwxrwxrwx 1 root root  9 Dec 18 20:36 ata-ST1000LM024_HN-M101MBB_S314JA0FB14082 -> ../../sda
lrwxrwxrwx 1 root root 10 Dec 18 20:36 ata-ST1000LM024_HN-M101MBB_S314JA0FB14082-part1 -> ../../sda1
lrwxrwxrwx 1 root root 10 Dec 18 20:36 ata-ST1000LM024_HN-M101MBB_S314JA0FB14082-part2 -> ../../sda2
lrwxrwxrwx 1 root root 10 Dec 18 20:36 ata-ST1000LM024_HN-M101MBB_S314JA0FB14082-part3 -> ../../sda3
lrwxrwxrwx 1 root root 10 Dec 18 20:36 ata-ST1000LM024_HN-M101MBB_S314JA0FB14082-part5 -> ../../sda5
lrwxrwxrwx 1 root root  9 Dec 18 20:36 wwn-0x50004cf20e9b00ff -> ../../sda
lrwxrwxrwx 1 root root 10 Dec 18 20:36 wwn-0x50004cf20e9b00ff-part1 -> ../../sda1
lrwxrwxrwx 1 root root 10 Dec 18 20:36 wwn-0x50004cf20e9b00ff-part2 -> ../../sda2
lrwxrwxrwx 1 root root 10 Dec 18 20:36 wwn-0x50004cf20e9b00ff-part3 -> ../../sda3
lrwxrwxrwx 1 root root 10 Dec 18 20:36 wwn-0x50004cf20e9b00ff-part5 -> ../../sda5
*********************** END /dev/disk/by-id

*********************** BEGIN /dev/disk/by-uuid
total 0
lrwxrwxrwx 1 root root 10 Dec 18 20:36 150bbed2-e29e-4a96-8f9e-6e993e22df04 -> ../../sda3
lrwxrwxrwx 1 root root 10 Dec 18 20:36 8E625C82625C7147 -> ../../sda5
lrwxrwxrwx 1 root root 10 Dec 18 20:36 8e1660b4-b7d1-4686-8939-f64d328ea13d -> ../../sda2
lrwxrwxrwx 1 root root 10 Dec 18 20:36 c5c12eeb-c91b-4dc0-9bf0-be761e43af8f -> ../../sda1
*********************** END /dev/disk/by-uuid

-- System Information:
Debian Release: 8.2
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.16.0-4-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_IN.utf8, LC_CTYPE=en_IN.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages grub-common depends on:
ii  gettext-base        0.19.3-2
ii  libc6               2.19-18+deb8u1
ii  libdevmapper1.02.1  2:1.02.90-2.2
ii  libfreetype6        2.5.2-3+deb8u1
ii  libfuse2            2.9.3-15+deb8u1
ii  liblzma5            5.1.1alpha+20120614-2+b3
ii  libpng12-0          1.2.50-2+deb8u1
ii  zlib1g              1:1.2.8.dfsg-2+b1

Versions of packages grub-common recommends:
ii  os-prober  1.65

Versions of packages grub-common suggests:
ii  console-setup  1.123
ii  desktop-base   8.0.2
pn  grub-emu       <none>
pn  multiboot-doc  <none>
pn  xorriso        <none>

-- no debconf information



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