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+## SignedJwt-PrivEsc
+---
+
+This tool specifically targets the `iam.serviceAccounts.signJwt` permission to generate an Access Token for a target Service Account without needing its private key.
+
+### OverView
+---
+
+In GCP, if an identity has the Service Account Token Creator role (or specifically iam.serviceAccounts.signJwt), they can sign a well-formed JWT which can be used to request Access Token for service Accounts. This script works as follows:
+
+   - Constructs an unsigned JWT with the target ServiceAccount as the issuer
+   - Calls the `signJwt` method of the IAM API, and passes the constructed JWT as the payload
+   - Exchanges the signed JWT for a full OAuth2 Access Token.
+
+
+### Options
+---
+
+```shell
+usage: signedjwt-privesc.py [-h] (-t TOKEN | -f TOKEN_FILE | -k KEY_FILE) -s TARGET
+
+Own Accounts with signJwt
+
+options:
+  -h, --help            show this help message and exit
+  -t, --token TOKEN     Caller's Access Token string
+  -f, --token-file TOKEN_FILE
+                        Path to file containing Access Token
+  -k, --key-file KEY_FILE
+                        Path to Service Account JSON key file
+  -s, --target-account TARGET   Target Service Account Email
+```
+
+
+### Prerequisites
+---
+    - Python 3.x
+    - The iamcredentials.googleapis.com API must be enabled in the target project.
+    - Your caller identity must have iam.serviceAccounts.signJwt permission on the target account.
+
+
+### Installation
+---
+
+```
+git clone https://github.com/5epi0l/signedJwt-PrivEsc.git
+cd signedJwt-PrivEsc
+pip install -r requirements.txt
+```
+
+### Usage
+---
+
+1. Using a direct Access Token
+
+```shell
+python3 signedjwt-privesc.py -t $(gcloud auth print-access-token) -s target-sa@project-id.iam.gserviceaccount.com
+```
+
+2. Using a Service Account JSON Key
+
+```shell
+python3 signedjwt-privesc.py -k /path/to/key.json -s target-sa@project-id.iam.gserviceaccount.com
+```
+
+3. Using a Token File
+
+```shell
+python3 signedjwt-privesc.py -f ./token.txt -s target-sa@project-id.iam.gserviceaccount.com
+```
+
+
+## Disclaimer
+---
+
+This tool is for authorized security auditing and educational purposes only. Unauthorized access to computer systems is illegal.
+