diff --git a/src/mod/applications/mod_http_cache/aws.c b/src/mod/applications/mod_http_cache/aws.c
index 17d6a233ab..cb6db5cb58 100644
--- a/src/mod/applications/mod_http_cache/aws.c
+++ b/src/mod/applications/mod_http_cache/aws.c
@@ -44,7 +44,7 @@
 int aws_s3_is_s3_url(const char *url)
 {
 	/* AWS bucket naming rules are complex... this match only supports virtual hosting of buckets */
-	return !zstr(url) && switch_regex_match(url, "^https?://[a-z0-9][-a-z0-9.]{1,61}[a-z0-9]\\.s3\\.amazonaws\\.com/.*$") == SWITCH_STATUS_SUCCESS;
+	return !zstr(url) && switch_regex_match(url, "^https?://[a-z0-9_][-a-z0-9._]{1,61}[a-z0-9_]\\.s3\\.amazonaws\\.com/.*$") == SWITCH_STATUS_SUCCESS;
 }
 
 /**
diff --git a/src/mod/applications/mod_http_cache/test_aws/main.c b/src/mod/applications/mod_http_cache/test_aws/main.c
index 8610127bbe..6c361ca8f1 100644
--- a/src/mod/applications/mod_http_cache/test_aws/main.c
+++ b/src/mod/applications/mod_http_cache/test_aws/main.c
@@ -48,6 +48,7 @@ static void test_check_url(void)
 	ASSERT_TRUE(aws_s3_is_s3_url("https://bucket.s3.amazonaws.com/object"));
 	ASSERT_TRUE(aws_s3_is_s3_url("https://bucket.s3.amazonaws.com/recordings/1240fwjf8we.mp3"));
 	ASSERT_TRUE(aws_s3_is_s3_url("https://bucket.s3.amazonaws.com/en/us/8000/1232345.mp3"));
+	ASSERT_TRUE(aws_s3_is_s3_url("https://bucket_with_underscore.s3.amazonaws.com/en/us/8000/1232345.mp3"));
 	ASSERT_FALSE(aws_s3_is_s3_url("bucket.s3.amazonaws.com/object.ext"));
 	ASSERT_FALSE(aws_s3_is_s3_url("https://s3.amazonaws.com/bucket/object"));
 	ASSERT_FALSE(aws_s3_is_s3_url("http://s3.amazonaws.com/bucket/object"));