diff --git a/src/content/docs/rules/transform/url-rewrite/reference/fields-functions.mdx b/src/content/docs/rules/transform/url-rewrite/reference/fields-functions.mdx
index e0770b369667fc..5a994edc856386 100644
--- a/src/content/docs/rules/transform/url-rewrite/reference/fields-functions.mdx
+++ b/src/content/docs/rules/transform/url-rewrite/reference/fields-functions.mdx
@@ -29,3 +29,7 @@ A rewrite expression (that is, the expression that defines the dynamic URL rewri
 Refer to the [Fields reference](/ruleset-engine/rules-language/fields/reference/) for more information on these fields.
 
 The [`concat()`](/ruleset-engine/rules-language/functions/#concat), [`regex_replace()`](/ruleset-engine/rules-language/functions/#regex_replace), and [`wildcard_replace()`](/ruleset-engine/rules-language/functions/#wildcard_replace) functions can appear only **once** in a rewrite expression.
+
+:::note
+For security reasons, its not possible to rewrite the [/cdn-cgi/ endpoint](/fundamentals/reference/cdn-cgi-endpoint/).
+:::