Skip to content

Instantly share code, notes, and snippets.

Embed
What would you like to do?
Using error messages to decloak an S3 bucket. Uses soap, unicode, post, multipart, streaming and index listing as ways of figure it out. You do need a valid aws-key (never the secret) to properly get the error messages
#!/bin/bash
# Written by Frans Rosén (twitter.com/fransrosen)
_debug="$2" #turn on debug
_timeout="20"
#you need a valid key, since the errors happens after it validates that the key exist. we do not need the secret key, only access key
_aws_key="AKIA..."
H_ACCEPT="accept-language: en-US,en;q=0.9,sv;q=0.8,zh-TW;q=0.7,zh;q=0.6,fi;q=0.5,it;q=0.4,de;q=0.3"
H_AGENT="user-agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.146 Safari/537.36"
_sed_bin=$(which gsed)
if [ "${_sed_bin}" == "" ]; then
_sed_bin=$(which sed)
fi
_timeout_bin=$(which gtimeout)
if [ "${_timeout_bin}" == "" ]; then
_timeout_bin=$(which timeout)
fi
r=$(echo "$1" | ${_sed_bin} -E 's/^[a-z]+:\/\///') #raw but without protocol
d=$(echo "$r" | cut -d "/" -f 1) #domain
pr=$(echo "$1" | ${_sed_bin} -E 's/(^[a-z]+:\/\/)?.*/\1/') #protocol, could be empty, use http if so
if [ "$pr" == "" ]; then pr="http://"; fi
pd="${pr}${d}" #protocol and domain always and only
u=$(echo "$1") #full url
p="${pr}$(echo "${r}" | rev | cut -d "/" -f 2- | rev)" # path without trailing slash (will be weird when bucket is in dir, but will be found later on)
result() {
echo "$1" >> log-bd-view.txt
[ "$1" != "" ] && echo "$1" && exit 0;
}
debug() {
echo "* $1" >> log-bd-view.txt
[ "$_debug" != "" ] && echo "* $1"
}
is_bucket_already() {
_no_protocol=$(echo "$1" | ${_sed_bin} -E 's/^[a-z]+:\/\///') # function is reused after, make sure we clean up proto
_comp=$(echo "${_no_protocol}" | grep -vE "^[^:]*s3[^:]+amazonaws.*") #check if domain contains s3.*amazonaws.com
if [ "${_comp}" == "" ]; then
result $(echo "${_no_protocol}" | grep -E '^s3.*amazon[^/]+\/.*' | cut -d "/" -f 2)
result $(echo "${_no_protocol}" | grep -E '^[^:]+.s3.*amazon.*' | ${_sed_bin} -E 's/^([^\:]+).s3[^:]+amazon.*$/\1/');
fi
}
is_bucket() {
debug "checking if bucket: ${1}..."
_response=$(${_timeout_bin} ${_timeout} curl -H "${H_ACCEPT}" -H "${H_AGENT}" "${1}" -sL -D- --insecure --max-time 5 | \
grep -iE "^x-amz-error-code|^server: amazons3|<Code>AccessDenied</Code>|Code: AccessDenied|NoSuchKey")
}
is_bucket_soap() {
debug "checking if bucket using soap... ${1}/soap"
_response=$(${_timeout_bin} ${_timeout} curl -H "${H_ACCEPT}" -H "${H_AGENT}" "${1}/soap" -X POST -sL -D- --insecure --max-time 5 | \
grep ">Missing SOAPAction header<")
}
is_bucket_invalid_char() {
debug "checking if bucket using invalid char: ${1}/%83..."
_response=$(${_timeout_bin} ${_timeout} curl -H "${H_ACCEPT}" -H "${H_AGENT}" "${1}/%83" -sL -D- --insecure --max-time 5 | \
grep -iE "<Code>InvalidURI</Code>|Code: InvalidURI|NoSuchKey")
}
is_bucket_invalid_method() {
debug "checking if bucket using invalid method... ${1}/xyz"
_response=$(${_timeout_bin} ${_timeout} curl -H "${H_ACCEPT}" -H "${H_AGENT}" "${1}/xyz" -X POSTX -sL -D- --insecure --max-time 5 | \
grep "<Code>BadRequest</Code><Message>")
if [ "${_response}" != "" ]; then
_response="${1}/xyz"
else
_response=""
fi
}
is_bucket_listable() {
debug "checking if bucket is listable... ${1}/?abc"
_response=$(${_timeout_bin} ${_timeout} curl -H "${H_ACCEPT}" -H "${H_AGENT}" -sL "${1}/?abc" --insecure --max-time 5 | \
grep "<ListBucketResult" -A 1 | grep -Eo "<Name>[^<]+</Name>" | cut -d ">" -f 2 | cut -d "<" -f 1)
}
is_bucket_domain() {
debug "checking if domain exists as bucket: http://${1}.s3.amazonaws.com..."
_response=$(${_timeout_bin} ${_timeout} curl -H "${H_ACCEPT}" -H "${H_AGENT}" "http://${1}.s3.amazonaws.com" -sL --insecure --max-time 5 | grep -E "ListBucketResult|AccessDenied|PermanentRedirect")
}
is_bucket_redirectable() {
debug "checking if url redirects to bucket... ${1}/xyzadad"
_response=$(${_timeout_bin} ${_timeout} curl -H "${H_ACCEPT}" -H "${H_AGENT}" -sL "$1/xyzadad" -D- | grep -i "^location:" | grep amazonaws | cut -d " " -f 2)
_response=$(is_bucket_already "${_response}") #remove s3-domain stuff
}
is_redirecting() {
debug "check if URL redirects to other domain... ${1}"
_response=$(curl -Ls -o /dev/null -H "${H_ACCEPT}" -H "${H_AGENT}" -w %{url_effective} "${1}")
_od=$(echo "${1}" | ${_sed_bin} -E 's/^[a-z]+:\/\///' | cut -d "/" -f 1)
_rd=$(echo "${_response}" | ${_sed_bin} -E 's/^[a-z]+:\/\///' | cut -d "/" -f 1)
if [ "${_od}" == "${_rd}" ]; then
_response=""
fi
}
bucket_unicode_sign_error() {
debug "checking unicode-error... ${1}/åäö"
_response=$(${_timeout_bin} ${_timeout} curl -H "${H_ACCEPT}" -H "${H_AGENT}" -sL "${1}/åäö" --insecure --max-time 5 | grep "host:" | grep "amazonaws.com" | cut -d ":" -f 2)
_response=$(is_bucket_already "${_response}") #remove s3-domain stuff
}
bucket_post_sign_error() {
debug "checking post-error... ${1}/okok?456"
_response=$(${_timeout_bin} ${_timeout} curl -H "${H_ACCEPT}" -H "${H_AGENT}" "${1}/okok?456" -H "Authorization: AWS ${_aws_key}:x" -H \
"Date: $(date -u +%a,\ %d\ %b\ %Y\ %H:%M:%S\ GMT)" -sL | \
grep "</StringToSign>" | \
cut -d "<" -f 1 | cut -d "/" -f 2)
}
bucket_get_sign_error() {
debug "checking get-error... ${1}/okok?AWSAccessKey..."
_response=$(${_timeout_bin} ${_timeout} curl -X GET -H "${H_ACCEPT}" -H "${H_AGENT}" "${1}/okok?AWSAccessKeyId=${_aws_key}&Expires=$(expr $(date +%s) + 1000)&Signature=x" -H \
"Date: $(date -u +%a,\ %d\ %b\ %Y\ %H:%M:%S\ GMT)" -sL | \
grep "</StringToSign>" | \
cut -d "<" -f 1 | cut -d "/" -f 2)
}
bucket_put_sign_error() {
debug "checking put-error... ${1}/okok?AWSAccessKey..."
_response=$(${_timeout_bin} ${_timeout} curl -X PUT -H "${H_ACCEPT}" -H "${H_AGENT}" "${1}/okok?AWSAccessKeyId=${_aws_key}&Expires=$(expr $(date +%s) + 1000)&Signature=x" -H \
"Date: $(date -u +%a,\ %d\ %b\ %Y\ %H:%M:%S\ GMT)" -sL | \
grep "</StringToSign>" | \
cut -d "<" -f 1 | cut -d "/" -f 2)
}
bucket_multipart_sign_error() {
debug "checking multipart-error... ${1}/?789"
_response=$(${_timeout_bin} ${_timeout} curl -H "${H_ACCEPT}" -H "${H_AGENT}" --form "d=x" -X POST "${1}/?789" \
-H "Authorization: AWS ${_aws_key}:x" -H \
"Date: $(date -u +%a,\ %d\ %b\ %Y\ %H:%M:%S\ GMT)" -sL | \
grep "</StringToSign>" | cut -d "<" -f 1 | cut -d "/" -f 2)
}
bucket_streaming_sign_error() {
debug "checking streaming sign-error... ${1}/ioioio?987"
_response=$(${_timeout_bin} ${_timeout} curl -H "${H_ACCEPT}" -H "${H_AGENT}" "${1}/ioio?987" -sL -H \
"Authorization: AWS4-HMAC-SHA256 Credential=${_aws_key}/20180101/ap-south-1/s3/aws4_request,SignedHeaders=date;host;x-amz-acl;x-amz-content-sha256;x-amz-date,Signature=x" -H \
"Date: $(date -u +%a,\ %d\ %b\ %Y\ %H:%M:%S\ GMT)" -H \
"x-amz-content-sha256: STREAMING-AWS4-HMAC-SHA256-PAYLOAD" | grep "<CanonicalRequest>" -A 1 | tail -n 1 | cut -d "/" -f 2)
}
change_bucket_location() {
debug "changing location of bucket... ${1}"
p="$1"
_response="1"
}
debug "start checking... ${u}"
is_bucket_already "${r}"
is_bucket "${pd}"
[ "${_response}" == "" ] && is_bucket_soap "${pd}"
_is_root_bucket="${_response}"
_bucket_location=""
if [ "${_is_root_bucket}" != "" ]; then
_bucket_location="${pd}"
else
is_bucket_soap "${p}"
[ "${_response}" == "" ] && is_bucket "${p}"
[ "${_response}" == "" ] && is_bucket "${p}/xyzabc" && change_bucket_location "${p}/xyzabc"
[ "${_response}" == "" ] && is_bucket_invalid_method "${p}"
[ "${_response}" == "" ] && is_bucket_invalid_char "${p}"
if [ "${_response}" != "" ]; then
_bucket_location="${p}"
fi
fi
if [ "${_bucket_location}" != "" ]; then
debug "bucket-location: ${_bucket_location}"
bucket_unicode_sign_error "${_bucket_location}"
result "${_response}"
bucket_streaming_sign_error "${_bucket_location}"
result "${_response}"
bucket_get_sign_error "${_bucket_location}"
result "${_response}"
bucket_post_sign_error "${_bucket_location}"
result "${_response}"
bucket_put_sign_error "${_bucket_location}"
result "${_response}"
bucket_multipart_sign_error "${_bucket_location}" #this one can bug out with fastly, since host is being different when POST
result "${_response}"
is_bucket_listable "${_bucket_location}"
result "${_response}"
is_bucket_redirectable "${_bucket_location}"
result "${_response}"
fi
#if [ "${_is_root_bucket}" ]; then
is_bucket_domain "${d}"
[ "${_response}" != "" ] && result "${d}"
#fi
is_redirecting "${pr}${r}"
[ "${_response}" != "" ] && bash $0 "${_response}" "$2" || debug "location is not a bucket: ${pr}${r} (${_bucket_location})" && exit 1
exit 0
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment