If an attacker successfully reads this file, they gain the identity of the user running that process. Because many developers accidentally grant excessive permissions to their EC2 instances or web servers, these leaked keys often provide enough access to: Spin up expensive crypto-mining instances. Exfiltrate sensitive data from S3 buckets. Delete entire production environments. How to Defend Your Infrastructure
However, improper handling of this file can lead to severe security risks, often highlighted in penetration testing scenarios or security audit reports referencing paths like -file-..-2F..-2F..-2F..-2Fhome-2F-2A-2F.aws-2Fcredentials .
: Use a "whitelist" of permitted file names or extensions. Never trust user input to define a path.
: Create new IAM users or backdoors while they have access. 3. AWS Native Credential Reports
| Obfuscated Part | Decoded Meaning | |----------------|----------------| | -file- | Likely indicates a file operation or parameter name (e.g., ?file=... ) | | ..-2F | ../ – the classic “parent directory” traversal sequence | | Repeated four times ..-2F..-2F..-2F..-2F | ../../../../ – move up four directory levels | | home-2F | home/ | | -2A-2F | */ – an asterisk wildcard, often used in shell paths or to match any username | | .aws-2Fcredentials | .aws/credentials – the default AWS CLI credentials file |
Instead of storing keys in ~/.aws/credentials on an EC2 instance, use .
Never trust user input. Use "allow-lists" for file names and ensure that any input containing ../ or encoded slashes is blocked or stripped. Most modern web frameworks provide built-in protection against path traversal. 2. Use IAM Roles (The "No Credentials" Rule)
A single unvalidated input field can be the difference between a functional app and a catastrophic breach. By understanding how attackers use simple traversal patterns to hunt for cloud keys, you can build more resilient, "secret-less" architectures.
GET /download?-file-..-2F..-2F..-2F..-2Fhome-2F-2A-2F.aws-2Fcredentials HTTP/1.1 Host: target.com
In the world of cloud security, the most dangerous distance isn't between two networks—it’s the few characters between a legitimate file request and your root directory. Specifically, the pattern ../../../../home/*/.aws/credentials has become a "holy grail" for attackers looking to pivot from a simple web vulnerability to total cloud takeover. What is this Attack Pattern?
: A web application accepts user input to display files (e.g., https://example.com ).
Review file permissions, utilize IAM roles, and monitor for unauthorized access attempts to sensitive files and resources.
: Require Session Tokens for metadata access, which stops most SSRF and LFI-based credential theft.
The story wasn’t about a hacker. It was about a loop .
The payload uses directory traversal sequences ( ../ or encoded as ..-2F ) to "break out" of the intended application directory and access the root filesystem. The goal is to reach the .aws/credentials file, which contains plain-text aws_access_key_id and aws_secret_access_key tokens. Write-up: Exfiltrating AWS Credentials via Path Traversal : Path Traversal / Arbitrary File Read. Target File : /home/[user]/.aws/credentials . Payload Mechanism :
If an attacker successfully retrieves this file via a path traversal vulnerability, they gain direct access to the organization's AWS environment. Depending on the permissions tied to those keys, the consequences can include:
[default] aws_access_key_id = AKIAIOSFODNN7EXAMPLE aws_secret_access_key = wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY
: Decodes to home/*/' . The asterisk ( * ) is a wildcard used to guess or scan across all user directories on a Linux system.
Mitigations and best practices