diff --git a/x-pack/plugin/core/src/main/java/org/elasticsearch/license/License.java b/x-pack/plugin/core/src/main/java/org/elasticsearch/license/License.java
index b2130ac9f4b81..158c0eb7b2e63 100644
--- a/x-pack/plugin/core/src/main/java/org/elasticsearch/license/License.java
+++ b/x-pack/plugin/core/src/main/java/org/elasticsearch/license/License.java
@@ -469,9 +469,17 @@ public static License fromXContent(XContentParser parser) throws IOException {
         }
         // not a license spec
         if (builder.signature != null) {
-            byte[] signatureBytes = Base64.getDecoder().decode(builder.signature);
-            ByteBuffer byteBuffer = ByteBuffer.wrap(signatureBytes);
-            int version = byteBuffer.getInt();
+            int version;
+            // In case the signature is truncated/malformed we might end up with fewer than 4 bytes in the byteBuffer
+            // or with a string that cannot be base64 decoded. In either case return a more friendly error instead of
+            // just throwing the BufferUnderflowException or the IllegalArgumentException
+            try {
+                byte[] signatureBytes = Base64.getDecoder().decode(builder.signature);
+                ByteBuffer byteBuffer = ByteBuffer.wrap(signatureBytes);
+                version = byteBuffer.getInt();
+            } catch (Exception e) {
+                throw new ElasticsearchException("malformed signature for license [" + builder.uid + "]", e);
+            }
             // we take the absolute version, because negative versions
             // mean that the license was generated by the cluster (see TrialLicense)
             // and positive version means that the license was signed
diff --git a/x-pack/plugin/core/src/test/java/org/elasticsearch/license/LicenseTests.java b/x-pack/plugin/core/src/test/java/org/elasticsearch/license/LicenseTests.java
new file mode 100644
index 0000000000000..e6cc8f2bd89f2
--- /dev/null
+++ b/x-pack/plugin/core/src/test/java/org/elasticsearch/license/LicenseTests.java
@@ -0,0 +1,118 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+package org.elasticsearch.license;
+
+import org.elasticsearch.ElasticsearchException;
+import org.elasticsearch.common.bytes.BytesArray;
+import org.elasticsearch.common.xcontent.XContentType;
+import org.elasticsearch.test.ESTestCase;
+
+import java.nio.BufferUnderflowException;
+import java.nio.charset.StandardCharsets;
+
+import static org.hamcrest.CoreMatchers.containsString;
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.CoreMatchers.instanceOf;
+
+public class LicenseTests extends ESTestCase {
+
+    public void testFromXContent() throws Exception {
+
+        String licenseString = "{\"license\":" +
+            "{\"uid\":\"4056779d-b823-4c12-a9cb-efa4a8d8c422\"," +
+            "\"type\":\"gold\"," +
+            "\"issue_date_in_millis\":1546589020459," +
+            "\"expiry_date_in_millis\":1546596340459," +
+            "\"max_nodes\":5," +
+            "\"issued_to\":\"customer\"," +
+            "\"issuer\":\"elasticsearch\"," +
+            "\"signature\":\"AAAAAgAAAA34V2kfTJVtvdL2LttwAAABmFJ6NGRnbEM3WVQrZVQwNkdKQmR1VytlMTMyM1J0dTZ1WGwyY2ZCVFhqMGtJU2gzZ3pnNTVpOW" +
+            "F5Y1NaUkwyN2VsTEtCYnlZR2c5WWtjQ0phaDlhRjlDUXViUmUwMWhjSkE2TFcwSGdneTJHbUV4N2RHUWJxV20ybjRsZHRzV2xkN0ZmdDlYblJmNVcxMlBWeU81" +
+            "V1hLUm1EK0V1dmF3cFdlSGZzTU5SZE1qUmFra3JkS1hCanBWVmVTaFFwV3BVZERzeG9Sci9rYnlJK2toODZXY09tNmFHUVNUL3IyUHExV3VSTlBneWNJcFQ0bX" +
+            "l0cmhNNnRwbE1CWE4zWjJ5eGFuWFo0NGhsb3B5WFd1eTdYbFFWQkxFVFFPSlBERlB0eVVJYXVSZ0lsR2JpRS9rN1h4MSsvNUpOcGN6cU1NOHN1cHNtSTFIUGN1" +
+            "bWNGNEcxekhrblhNOXZ2VEQvYmRzQUFwbytUZEpRR3l6QU5oS2ZFSFdSbGxxNDZyZ0xvUHIwRjdBL2JqcnJnNGFlK09Cek9pYlJ5Umc9PQAAAQAth77fQLF7CC" +
+            "EL7wA6Z0/UuRm/weECcsjW/50kBnPLO8yEs+9/bPa5LSU0bF6byEXOVeO0ebUQfztpjulbXh8TrBDSG+6VdxGtohPo2IYPBaXzGs3LOOor6An/lhptxBWdwYmf" +
+            "bcp0m8mnXZh1vN9rmbTsZXnhBIoPTaRDwUBi3vJ3Ms3iLaEm4S8Slrfmtht2jUjgGZ2vAeZ9OHU2YsGtrSpz6f\"}";
+        License license = License.fromSource(new BytesArray(licenseString.getBytes(StandardCharsets.UTF_8)),
+            XContentType.JSON);
+        assertThat(license.type(), equalTo("gold"));
+        assertThat(license.uid(), equalTo("4056779d-b823-4c12-a9cb-efa4a8d8c422"));
+        assertThat(license.issuer(), equalTo("elasticsearch"));
+        assertThat(license.issuedTo(), equalTo("customer"));
+        assertThat(license.expiryDate(), equalTo(1546596340459L));
+        assertThat(license.issueDate(), equalTo(1546589020459L));
+    }
+
+    public void testNotEnoughBytesFromXContent() throws Exception {
+
+        String licenseString = "{\"license\": " +
+            "{\"uid\":\"4056779d-b823-4c12-a9cb-efa4a8d8c422\"," +
+            "\"type\":\"gold\"," +
+            "\"issue_date_in_millis\":1546589020459," +
+            "\"expiry_date_in_millis\":1546596340459," +
+            "\"max_nodes\":5," +
+            "\"issued_to\":\"customer\"," +
+            "\"issuer\":\"elasticsearch\"," +
+            "\"signature\":\"AA\"}" +
+            "}";
+        ElasticsearchException exception =
+            expectThrows(ElasticsearchException.class,
+                () -> {
+                    License.fromSource(new BytesArray(licenseString.getBytes(StandardCharsets.UTF_8)),
+                        XContentType.JSON);
+                });
+        assertThat(exception.getMessage(), containsString("malformed signature for license [4056779d-b823-4c12-a9cb-efa4a8d8c422]"));
+        assertThat(exception.getCause(), instanceOf(BufferUnderflowException.class));
+    }
+
+    public void testMalformedSignatureFromXContent() throws Exception {
+
+        String licenseString = "{\"license\": " +
+            "{\"uid\":\"4056779d-b823-4c12-a9cb-efa4a8d8c422\"," +
+            "\"type\":\"gold\"," +
+            "\"issue_date_in_millis\":1546589020459," +
+            "\"expiry_date_in_millis\":1546596340459," +
+            "\"max_nodes\":5," +
+            "\"issued_to\":\"customer\"," +
+            "\"issuer\":\"elasticsearch\"," +
+            "\"signature\":\"" + randomAlphaOfLength(10) + "\"}" +
+            "}";
+        ElasticsearchException exception =
+            expectThrows(ElasticsearchException.class,
+                () -> {
+                    License.fromSource(new BytesArray(licenseString.getBytes(StandardCharsets.UTF_8)),
+                        XContentType.JSON);
+                });
+    }
+
+    public void testUnableToBase64DecodeFromXContent() throws Exception {
+
+        String licenseString = "{\"license\":" +
+            "{\"uid\":\"4056779d-b823-4c12-a9cb-efa4a8d8c422\"," +
+            "\"type\":\"gold\"," +
+            "\"issue_date_in_millis\":1546589020459," +
+            "\"expiry_date_in_millis\":1546596340459," +
+            "\"max_nodes\":5," +
+            "\"issued_to\":\"customer\"," +
+            "\"issuer\":\"elasticsearch\"," +
+            "\"signature\":\"AAAAAgAAAA34V2kfTJVtvdL2LttwAAABmFJ6NGRnbEM3WVQrZVQwNkdKQmR1VytlMTMyM1J0dTZ1WGwyY2ZCVFhqMGtJU2gzZ3pnNTVpOW" +
+            "F5Y1NaUkwyN2VsTEtCYnlZR2c5WWtjQ0phaDlhRjlDUXViUmUwMWhjSkE2TFcwSGdneTJHbUV4N2RHUWJxV20ybjRsZHRzV2xkN0ZmdDlYblJmNVcxMlBWeU81" +
+            "V1hLUm1EK0V1dmF3cFdlSGZzTU5SZE1qUmFra3JkS1hCanBWVmVTaFFwV3BVZERzeG9Sci9rYnlJK2toODZXY09tNmFHUVNUL3IyUHExV3VSTlBneWNJcFQ0bX" +
+            "l0cmhNNnRwbE1CWE4zWjJ5eGFuWFo0NGhsb3B5WFd1eTdYbFFWQkxFVFFPSlBERlB0eVVJYXVSZ0lsR2JpRS9rN1h4MSsvNUpOcGN6cU1NOHN1cHNtSTFIUGN1" +
+            "bWNGNEcxekhrblhNOXZ2VEQvYmRzQUFwbytUZEpRR3l6QU5oS2ZFSFdSbGxxNDZyZ0xvUHIwRjdBL2JqcnJnNGFlK09Cek9pYlJ5Umc9PQAAAQAth77fQLF7CC" +
+            "EL7wA6Z0/UuRm/weECcsjW/50kBnPLO8yEs+9/bPa5LSU0bF6byEXOVeO0ebUQfztpjulbXh8TrBDSG+6VdxGtohPo2IYPBaXzGs3LOOor6An/lhptxBWdwYmf" +
+            "+xHAQ8tyvRqP5G+PRU7tiluEwR/eyHGZV2exdJNzmoGzdPSWwueBM5HK2GexORICH+UFI4cuGz444/hL2MMM1RdpVWQkT0SJ6D9x/VuSmHuYPdtX59Pp41LXvl" +
+            "bcp0m8mnXZh1vN9rmbTsZXnhBIoPTaRDwUBi3vJ3Ms3iLaEm4S8Slrfmtht2jUjgGZ2vAeZ9OHU2YsGtrSpz6fd\"}";
+        ElasticsearchException exception =
+            expectThrows(ElasticsearchException.class,
+                () -> {
+                    License.fromSource(new BytesArray(licenseString.getBytes(StandardCharsets.UTF_8)),
+                        XContentType.JSON);
+                });
+        assertThat(exception.getMessage(), containsString("malformed signature for license [4056779d-b823-4c12-a9cb-efa4a8d8c422]"));
+        assertThat(exception.getCause(), instanceOf(IllegalArgumentException.class));
+    }
+}