# Padding-Oracle-Attacker | CLI Tool And Library To Execute Padding Oracle Attacks Easily

**URL:** <https://onehack.st/t/padding-oracle-attacker-cli-tool-and-library-to-execute-padding-oracle-attacks-easily/96246>\
**Category:** Tools & Scripts\
**Tags:** tools, hacking, hosting\
**Created:** [July 15, 2020, 12:02pm UTC](https://onehack.st/t/padding-oracle-attacker-cli-tool-and-library-to-execute-padding-oracle-attacks-easily/96246 "2020-07-15T12:02:54Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![BlueHacker](https://onehack.st/user_avatar/onehack.st/bluehacker/32/174721_2.png) [@BlueHacker](https://onehack.st/u/BlueHacker)\
**Post date:** [July 15, 2020, 12:02pm UTC](https://onehack.st/t/padding-oracle-attacker-cli-tool-and-library-to-execute-padding-oracle-attacks-easily/96246/1 "2020-07-15T12:02:54Z")

</div>

![](https://raw.githubusercontent.com/KishanBagaria/padding-oracle-attacker/master/media/poattack-decrypt.gif)

CLI tool and library to execute [padding oracle attacks](https://en.wikipedia.org/wiki/Padding_oracle_attack) easily, with support for concurrent network requests and an elegant UI.

**Install**  
Make sure [Node.js](https://nodejs.org/) is installed, then run

```auto
$ npm install --global padding-oracle-attacker

```

or

```auto
$ yarn global add padding-oracle-attacker

```

**CLI Usage**

```auto
Usage $ padding-oracle-attacker decrypt <url> hex:<ciphertext_hex> <block_size> <error> [options] $ padding-oracle-attacker decrypt <url> b64:<ciphertext_b64> <block_size> <error> [options] $ padding-oracle-attacker encrypt <url> <plaintext> <block_size> <error> [options] $ padding-oracle-attacker encrypt <url> hex:<plaintext_hex> <block_size> <error> [options] $ padding-oracle-attacker analyze <url> [<block_size>] [options]Commands decrypt Finds the plaintext (foobar) for given ciphertext (hex:0123abcd) encrypt Finds the ciphertext (hex:abcd1234) for given plaintext (foo=bar) analyze Helps find out if the URL is vulnerable or not, and how the response differs when a decryption error occurs (for the <error> argument)Arguments <url> URL to attack. Payload will be inserted at the end by default. To specify a custom injection point, include {POPAYLOAD} in a header (-H), request body (-d) or the URL <block_size> Block size used by the encryption algorithm on the server <error> The string present in response when decryption fails on the server. Specify a string present in the HTTP response body (like PaddingException) or status code of the HTTP response (like 400)Options -c, --concurrency Requests to be sent concurrently [default: 128] --disable-cache Disable network cache. Saved to [default: false] poattack-cache.json.gz.txt by default -X, --method HTTP method to use while making request [default: GET] -H, --header Headers to be sent with request. -H 'Cookie: cookie1' -H 'User-Agent: Googlebot/2.1' -d, --data Request body JSON string: {"id": 101, "foo": "bar"} URL encoded: id=101&foo=bar Make sure to specify the Content-Type header. -e, --payload-encoding Ciphertext payload encoding for {POPAYLOAD} [defa ult: hex] base64 FooBar+/= base64-urlsafe FooBar-_ hex deadbeef hex-uppercase DEADBEEF base64(xyz) Custom base64 ('xyz' represent characters for '+/=') --dont-urlencode-payload Don't URL encode {POPAYLOAD} [default: false] --start-from-1st-block Start processing from the first block instead [default: false] of the last (only works with decrypt mode)Examples $ poattack decrypt http://localhost:2020/decrypt?ciphertext= hex:e3e70d8599206647dbc96952aaa209d75b4e3c494842aa1aa8931f51505df2a8a184e99501914312e2c50320835404e9 16 400 $ poattack encrypt http://localhost:2020/decrypt?ciphertext= "foo bar 🦄" 16 400 $ poattack encrypt http://localhost :2020/decrypt?ciphertext= hex:666f6f2062617220f09fa684 16 400 $ poattack analyze http://localhost:2020/decrypt?ciphertext=Aliases poattack padding-oracle-attack

```

**Library API**

```auto
const { decrypt, encrypt } = require('padding-oracle-attacker')// orimport { decrypt, encrypt } from 'padding-oracle-attacker'const { blockCount, totalSize, foundBytes, interBytes } = await decrypt(options)const { blockCount, totalSize, foundBytes, interBytes, finalRequest } = await encrypt(options)

```

**`decrypt(options: Object): Promise`**

**`encrypt(options: Object): Promise`**

**Required options**

**`url: string`**  
URL to attack. Payload will be appended at the end by default. To specify a custom injection point, include `{POPAYLOAD}` in the URL, a header ( `requestOptions.headers` ) or the request body ( `requestOptions.data` )

**`blockSize: number`**  
Block size used by the encryption algorithm on the server.

**`isDecryptionSuccess: ({ statusCode, headers, body }) => boolean`**  
Function that returns true if the server response indicates decryption was successful.

**`ciphertext: Buffer` ( `decrypt` only)**  
Ciphertext to decrypt.

**`plaintext: Buffer` ( `encrypt` only)**  
Plaintext to encrypt. Padding will be added automatically. Example: `Buffer.from('foo bar', 'utf8')`

**Optional options**

**`concurrency: number = 128`**  
Network requests to be sent concurrently.

**`isCacheEnabled: boolean = true`**  
Responses are cached by default and saved to `poattack-cache.json.gz.txt` . Set to `false` to disable caching.

**`requestOptions: { method, headers, data }`**

**`requestOptions.method: string`**  
HTTP method to use while making the request. `GET` by default. `POST` , `PUT` , `DELETE` are some valid options.

**`requestOptions.headers: { string: string }`**  
Headers to be sent with request. Example: `{ 'Content-Type': 'application/x-www-form-urlencoded' }`

**`requestOptions.body: string`**  
Request body. Can be a JSON string, URL encoded params etc. `Content-Type` header has to be set manually.

**`logMode: 'full'|'minimal'|'none' = 'full'`**  
`full` : Log everything to console (default)  
`minimal` : Log only after start and completion to console  
`none` : Log nothing to console

**`transformPayload: (ciphertext: Buffer) => string`**  
Function to convert the `ciphertext` into a string when making a request. By default, `ciphertext` is encoded in hex and inserted at the injection point (URL end unless `{POPAYLOAD}` is present).

**Optional options ( `decrypt` only)**

**`alreadyFound: Buffer`**  
Plaintext bytes already known/found that can be skipped (from the end). If you provide a `Buffer` of ten bytes, the last ten bytes will be skipped.

**`initFirstPayloadBlockWithOrigBytes: boolean = false`**  
Initialize first payload block with original `ciphertext` bytes instead of zeroes.  
Example: `abcdef12345678ff 1111111111111111` instead of `00000000000000ff 1111111111111111`

**`startFromFirstBlock: boolean = false`**  
Start processing from the first block instead of the last.

**`makeInitialRequest: boolean = true`**  
Make an initial request with the original `ciphertext` provided and log server response to console to allow the user to make sure network requests are being sent correctly.

**Optional options ( `encrypt` only)**

**`makeFinalRequest: boolean = true`**  
After finding the `ciphertext` bytes for the new `plaintext` , make a final request with the found bytes and log the server response to console.

**`lastCiphertextBlock: Buffer`**  
Custom ciphertext for the last block. Last block is just zeroes by default ( `000000000000000` ).

**Developing**  
`padding-oracle-attacker` is written in TypeScript. If you’d like to modify the source files and run them, you can either compile the files into JS first and run them using node, or use [ts-node](https://www.npmjs.com/package/ts-node).  
Example: `yarn build` then `node dist/cli ...` or simply `ts-node src/cli ...`

**`yarn build` or `npm run build`**  
Builds the TypeScript files inside the `src` directory to JS files and outputs them to the `dist` directory.

**`yarn clean` or `npm run clean`**  
Deletes the `dist` directory.

**`yarn lint` or `npm run lint`**  
Lints the files using eslint.

**`yarn test` or `npm run test`**  
Lints and runs the tests using ava.

**`node test/helpers/vulnerable-server.js`**  
Runs the test server which is vulnerable to padding oracle attacks at [http://localhost:2020](http://localhost:2020/)

**Related**

- [PadBuster](https://github.com/GDSSecurity/PadBuster) (Perl)
- [Padding Oracle Attack](https://github.com/mpgn/Padding-oracle-attack) (Python)
- [python-paddingoracle](https://github.com/mwielgoszewski/python-paddingoracle) (Python)
- [Poracle](https://github.com/iagox86/poracle) (Ruby)
- [GoPaddy](https://github.com/glebarez/GoPaddy) (Go)
- [pax](https://github.com/liamg/pax) (Go)

## GitHub:

[https://github.com/KishanBagaria/padding-oracle-attacker](https://github.com/KishanBagaria/padding-oracle-attacker)