diff --git a/libs/core/src/test/java/org/elasticsearch/core/GlobTests.java b/libs/core/src/test/java/org/elasticsearch/core/GlobTests.java
index f37dfb47c6591..1025b8d42e7ca 100644
--- a/libs/core/src/test/java/org/elasticsearch/core/GlobTests.java
+++ b/libs/core/src/test/java/org/elasticsearch/core/GlobTests.java
@@ -30,7 +30,7 @@ public void testMatchLiteral() {
         str = randomAlphanumericOfLength(randomIntBetween(1, 12));
         assertMatch(str, str);
 
-        str = randomAsciiString(randomIntBetween(1, 24), ch -> ch >= ' ' && ch <= '~' && ch != '*');
+        str = randomAsciiStringNoAsterisks(randomIntBetween(1, 24));
         assertMatch(str, str);
     }
 
@@ -67,7 +67,7 @@ public void testPrefixMatch() {
         assertNonMatch("123*", "abc123");
         assertNonMatch("123*", "abc123def");
 
-        var prefix = randomAsciiString(randomIntBetween(2, 12));
+        var prefix = randomAsciiStringNoAsterisks(randomIntBetween(2, 12));
         var pattern = prefix + "*";
         assertMatch(pattern, prefix);
         assertMatch(pattern, prefix + randomAsciiString(randomIntBetween(1, 30)));
@@ -92,7 +92,7 @@ public void testSuffixMatch() {
         assertNonMatch("*123", "123abc");
         assertNonMatch("*123", "abc123def");
 
-        var suffix = randomAsciiString(randomIntBetween(2, 12));
+        var suffix = randomAsciiStringNoAsterisks(randomIntBetween(2, 12));
         var pattern = "*" + suffix;
         assertMatch(pattern, suffix);
         assertMatch(pattern, randomAsciiString(randomIntBetween(1, 30)) + suffix);
@@ -114,7 +114,7 @@ public void testInfixStringMatch() {
         assertNonMatch("*123*", "12*");
         assertNonMatch("*123*", "1.2.3");
 
-        var infix = randomAsciiString(randomIntBetween(2, 12));
+        var infix = randomAsciiStringNoAsterisks(randomIntBetween(2, 12));
         var pattern = "*" + infix + "*";
         assertMatch(pattern, infix);
         assertMatch(pattern, randomAsciiString(randomIntBetween(1, 30)) + infix + randomAsciiString(randomIntBetween(1, 30)));
@@ -138,8 +138,8 @@ public void testInfixAsteriskMatch() {
         assertMatch("123*321", "12345678987654321");
         assertNonMatch("123*321", "12321");
 
-        var prefix = randomAsciiString(randomIntBetween(2, 12));
-        var suffix = randomAsciiString(randomIntBetween(2, 12));
+        var prefix = randomAsciiStringNoAsterisks(randomIntBetween(2, 12));
+        var suffix = randomAsciiStringNoAsterisks(randomIntBetween(2, 12));
         var pattern = prefix + "*" + suffix;
         assertMatch(pattern, prefix + suffix);
         assertMatch(pattern, prefix + randomAsciiString(randomIntBetween(1, 30)) + suffix);
@@ -180,6 +180,10 @@ private String randomAsciiString(int length) {
         return randomAsciiString(length, ch -> ch >= ' ' && ch <= '~');
     }
 
+    private String randomAsciiStringNoAsterisks(final int length) {
+        return randomAsciiString(length, ch -> ch >= ' ' && ch <= '~' && ch != '*');
+    }
+
     private String randomAsciiString(int length, CharPredicate validCharacters) {
         StringBuilder str = new StringBuilder(length);
         nextChar: for (int i = 0; i < length; i++) {