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36 lines
1.1 KiB
Markdown
36 lines
1.1 KiB
Markdown
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# TaintedSSRF
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Potential Server-Side Request Forgery vulnerability. This rule is emitted when user-controlled input can be passed into a network request.
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## Risk
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Passing untrusted user input to network requests could be dangerous.
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If an attacker can fully control a HTTP request they could connect to internal services. Depending on the nature of these, this can pose a security risk. (e.g. backend services, admin interfaces, AWS metadata, ...)
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## Example
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```php
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<?php
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$ch = curl_init();
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curl_setopt($ch, CURLOPT_URL, $_GET['url']);
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curl_exec($ch);
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curl_close($ch);
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```
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## Mitigations
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Mitigating SSRF vulnerabilities can be tricky. Disallowing IPs would likely not work as an attacker could create a malicious domain that points to an internal DNS name.
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Consider:
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1. Having an allow list of domains that can be connected to.
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2. Pointing cURL to a proxy that has no access to internal resources.
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## Further resources
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- [OWASP Wiki for Server Side Request Forgery](https://owasp.org/www-community/attacks/Server_Side_Request_Forgery)
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- [CWE-918](https://cwe.mitre.org/data/definitions/918)
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