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Protections against malicious activity

Applications and services on the internet experience frequent attacks, probes, and other malicious traffic. Threat actors making malicious requests may aim to exploit vulnerabilities, to compromise infrastructure, or to deny service to legitimate users.

As a multi-tenant platform, experiences a wide range of malicious activity and frequent attacks. To ensure your application remains online and unaffected, we continuously enhance our defenses. employs multiple layers of protection to safeguard against different types of attacks.

Blocking known malicious patterns

All inbound traffic to is protected by a comprehensive set of web application firewall (WAF) rules. These rules, which include both managed and custom rule sets, block traffic that matches malicious patterns.

Managed rule sets provided by AWS offer protection against:

  • Cross-site scripting (XSS)
  • Requests for invalid paths or extensions
  • Requests from known or suspected malicious IP ranges
  • Known Java exploits

Our custom rule set additionally blocks:

Protections against traffic surges occasionally encounters significant spikes, either due to DDoS or large scale probing. To mitigate the impact of such surges, we enforce rate limits on requests with a CHALLENGE action.

Vulnerability scans & CHALLENGE responses

Some site scanning or penetration testing tools may incorrectly flag responses that include an aws-waf-token cookie as a security vulnerability. This is a false positive and not indicative of a real vulnerability.

The CHALLENGE action responds to web requests with an interstitial page, allowing legitimate browsers to proceed while blocking requests from most bots. Successfully passing the CHALLENGE results in an aws-waf-token cookie, which stores the timestamp of the client’s last successful response. The presence of this cookie is evidence of our platform’s protective measures.

Since AWS handles the CHALLENGE response for requests exceeding the rate-limit threshold before reaching your application, these responses may not align with your normal application behavior. For example, CHALLENGE responses may not:

  • Redirect HTTP requests to HTTPS
  • Include headers normally returned by your application

AWS CloudFront & CDNs offers Amazon CloudFront as a CDN to enhance protection against traffic surges. CloudFront can cache requests, reducing the load on your application.

CloudFront CDNs managed by receive additional protections:

Reporting impact on legitimate traffic

If you suspect that your traffic is being improperly affected by these protections, please contact us at

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  • Last modified on: 2024-06-04

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