diff --git a/jdk/src/share/classes/sun/security/provider/certpath/AlgorithmChecker.java b/jdk/src/share/classes/sun/security/provider/certpath/AlgorithmChecker.java
index ab75ff00eef..4b6ff56cf40 100644
--- a/jdk/src/share/classes/sun/security/provider/certpath/AlgorithmChecker.java
+++ b/jdk/src/share/classes/sun/security/provider/certpath/AlgorithmChecker.java
@@ -75,7 +75,7 @@ final public class AlgorithmChecker extends PKIXCertPathChecker {
     private PublicKey prevPubKey;
 
     private final static Set<CryptoPrimitive> SIGNATURE_PRIMITIVE_SET =
-                                    EnumSet.of(CryptoPrimitive.SIGNATURE);
+        Collections.unmodifiableSet(EnumSet.of(CryptoPrimitive.SIGNATURE));
 
     private final static DisabledAlgorithmConstraints
         certPathDefaultConstraints = new DisabledAlgorithmConstraints(
diff --git a/jdk/src/share/classes/sun/security/ssl/SignatureAndHashAlgorithm.java b/jdk/src/share/classes/sun/security/ssl/SignatureAndHashAlgorithm.java
index 0d9f14cd5b8..9640ffb8589 100644
--- a/jdk/src/share/classes/sun/security/ssl/SignatureAndHashAlgorithm.java
+++ b/jdk/src/share/classes/sun/security/ssl/SignatureAndHashAlgorithm.java
@@ -68,7 +68,7 @@ final class SignatureAndHashAlgorithm {
 
     // performance optimization
     private final static Set<CryptoPrimitive> SIGNATURE_PRIMITIVE_SET =
-                                    EnumSet.of(CryptoPrimitive.SIGNATURE);
+        Collections.unmodifiableSet(EnumSet.of(CryptoPrimitive.SIGNATURE));
 
     // supported pairs of signature and hash algorithm
     private final static Map<Integer, SignatureAndHashAlgorithm> supportedMap;