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AWS AmazonCloudWatch medium security documentation change

Service: AmazonCloudWatch · 2025-03-12 · Security-related medium

File: AmazonCloudWatch/latest/monitoring/CloudWatch_Synthetics_Canaries_Troubleshoot.md

Summary

Changed AWS WAF configuration guidance from recommending custom user-agent strings to requiring a fixed 'CloudWatchSynthetics' string match condition

Security assessment

Addresses potential WAF misconfiguration that could block legitimate canary traffic. Explicitly recommends security configuration to prevent service disruption.

Diff

diff --git a/AmazonCloudWatch/latest/monitoring/CloudWatch_Synthetics_Canaries_Troubleshoot.md b/AmazonCloudWatch/latest/monitoring/CloudWatch_Synthetics_Canaries_Troubleshoot.md



index 0d770b615..3b4b68b19 100644
--- a/AmazonCloudWatch/latest/monitoring/CloudWatch_Synthetics_Canaries_Troubleshoot.md
+++ b/AmazonCloudWatch/latest/monitoring/CloudWatch_Synthetics_Canaries_Troubleshoot.md
@@ -131,12 +131 @@ Enter the following command to change the runtime management of the Lambda funct
-To allow canary traffic through AWS WAF,create a AWS WAF string match condition that allows a custom string that you specify. For more information, see [Working with string match conditions ](https://docs.aws.amazon.com/waf/latest/developerguide/classic-web-acl-string-conditions.html) in the AWS WAF documentation.
-
-We strongly recommend that you use your own custom user-agent string instead of using default values. This provides better control over AWS WAF filtering and improves security.
-
-To set a custom user-agent string, do the following:
-
-  * For Playwright runtimes, you can append your AWS WAF approved custom user-agent string using the Synthetics configuration file. For more information, see [CloudWatch Synthetics configurations](./Synthetics_WritingCanary_Nodejs_Playwright.html#Synthetics_canary_configure_Playwright_script).
-
-  * For Puppeteer or Selenium runtimes, you can add your custom user-agent string using supported library functions. For Puppeteer runtimes, see [async addUserAgent(page, userAgentString);](./CloudWatch_Synthetics_Canaries_Library_Nodejs.html#CloudWatch_Synthetics_Library_addUserAgent). For Selenium runtimes, see [ add_user_agent(user_agent_str)](./CloudWatch_Synthetics_Canaries_Library_Python.html#CloudWatch_Synthetics_Library_add_user_agent).
-
-
-
+To prevent AWS WAF from blocking your canary, set up a AWS WAF string match condition that allows the string `CloudWatchSynthetics`. For more information, see [Working with string match conditions ](https://docs.aws.amazon.com/waf/latest/developerguide/classic-web-acl-string-conditions.html) in the AWS WAF documentation.