first, there is a variable that contain special character on bash script. here is the example. list.txt :
user = root
password = 1234
Bash Script :
#!/bin/sh
var1 = var&2018+&
find . -name "list.txt" -exec sed -i "s/1234/"$var1"/g" {} +
when i executed the script, the result is : var12342018+1234.
Update 1 (answer by Oliv) :
var1='var&2018+&'
find . -name "*list.txt" -exec bash -c 'sed -i "s/1234/$2/g" $1' _ {} "$var1" \;
and the result still : password = var12342018+1234
maybe anyone can help me. thank you