Merge branch '4.0.x'

Closes gh-50184

Author: wilkinsona

core/spring-boot/src/main/java/org/springframework/boot/env/RandomValuePropertySource.java

@@ -16,6 +16,7 @@
 
 package org.springframework.boot.env;
 
+import java.security.SecureRandom;
 import java.util.HexFormat;
 import java.util.OptionalInt;
 import java.util.OptionalLong;
@@ -79,7 +80,7 @@ public RandomValuePropertySource() {
 	}
 
 	public RandomValuePropertySource(String name) {
-		super(name, new Random());
+		super(name, new SecureRandom());
 	}
 
 	@Override

core/spring-boot/src/test/java/org/springframework/boot/env/RandomValuePropertySourceTests.java

@@ -50,7 +50,7 @@ void getPropertyWhenNotRandomReturnsNull() {
 
 	@Test
 	void getPropertyWhenStringReturnsValue() {
-		assertThat(this.source.getProperty("random.string")).isNotNull();
+		assertThat(this.source.getProperty("random.string")).isNotNull().asString().containsPattern("^[0-9a-f]{32}$");
 	}
 
 	@Test