diff --git a/base/acme/src/main/java/org/dogtagpki/acme/server/ACMEAccountService.java b/base/acme/src/main/java/org/dogtagpki/acme/server/ACMEAccountService.java
index b4d43fcf567..8c9f704cf5e 100644
--- a/base/acme/src/main/java/org/dogtagpki/acme/server/ACMEAccountService.java
+++ b/base/acme/src/main/java/org/dogtagpki/acme/server/ACMEAccountService.java
@@ -17,6 +17,8 @@
 import javax.ws.rs.core.Response.ResponseBuilder;
 import javax.ws.rs.core.UriInfo;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
+
 import org.dogtagpki.acme.ACMEAccount;
 import org.dogtagpki.acme.ACMEHeader;
 import org.dogtagpki.acme.ACMENonce;
@@ -72,28 +74,40 @@ public Response updateAccount(@PathParam("id") String accountID, JWS jws) throws
         engine.validateJWS(jws, header.getAlg(), account.getJWK());
 
         String payload = new String(jws.getPayloadAsBytes(), "UTF-8");
-        logger.info("Payload: " + payload);
-
-        ACMEAccount update = ACMEAccount.fromJSON(payload);
 
-        String newStatus = update.getStatus();
-        if (newStatus != null) {
-            logger.info("New status: " + newStatus);
-            account.setStatus(newStatus);
+        if (payload.isEmpty()) {
+            logger.info("Empty payload; treating as POST-as-GET");
         }
 
-        String[] newContact = update.getContact();
-        if (newContact != null) {
-            logger.info("New contact:");
-            for (String c : newContact) {
-                logger.info("- " + c);
+        else {
+            logger.info("Payload: " + payload);
+
+            ACMEAccount update;
+            try {
+                update = ACMEAccount.fromJSON(payload);
+            } catch (JsonProcessingException e) {
+                throw engine.createMalformedException(e.toString());
             }
-            account.setContact(newContact);
-        }
 
-        engine.updateAccount(account);
+            String newStatus = update.getStatus();
+            if (newStatus != null) {
+                logger.info("New status: " + newStatus);
+                account.setStatus(newStatus);
+            }
+
+            String[] newContact = update.getContact();
+            if (newContact != null) {
+                logger.info("New contact:");
+                for (String c : newContact) {
+                    logger.info("- " + c);
+                }
+                account.setContact(newContact);
+            }
 
-        // TODO: if account is deactivated, cancel all account's pending operations
+            engine.updateAccount(account);
+
+            // TODO: if account is deactivated, cancel all account's pending operations
+        }
 
         // RFC 8555 Section 7.1.2.1 Orders List
         //
diff --git a/base/acme/src/main/java/org/dogtagpki/acme/server/ACMEEngine.java b/base/acme/src/main/java/org/dogtagpki/acme/server/ACMEEngine.java
index 938c9b76f47..92a8baa99a5 100644
--- a/base/acme/src/main/java/org/dogtagpki/acme/server/ACMEEngine.java
+++ b/base/acme/src/main/java/org/dogtagpki/acme/server/ACMEEngine.java
@@ -728,6 +728,18 @@ public Exception createAccountDoesNotExistException(String accountID) {
         return new WebApplicationException(builder.build());
     }
 
+    public Exception createMalformedException(String desc) {
+        ResponseBuilder builder = Response.status(Response.Status.BAD_REQUEST);
+        builder.type("application/problem+json");
+
+        ACMEError error = new ACMEError();
+        error.setType("urn:ietf:params:acme:error:malformed");
+        error.setDetail("Malformed request: " + desc);
+        builder.entity(error);
+
+        return new WebApplicationException(builder.build());
+    }
+
     public void updateAccount(ACMEAccount account) throws Exception {
         database.updateAccount(account);
     }