diff --git a/src/main/java/org/apache/nifi/NarMojo.java b/src/main/java/org/apache/nifi/NarMojo.java
index 56f059d..0533598 100644
--- a/src/main/java/org/apache/nifi/NarMojo.java
+++ b/src/main/java/org/apache/nifi/NarMojo.java
@@ -104,6 +104,7 @@
 import java.util.TreeSet;
 import java.util.jar.JarEntry;
 import java.util.jar.JarFile;
+import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 
 /**
@@ -122,6 +123,8 @@ public class NarMojo extends AbstractMojo {
     private static final String DOCUMENTATION_WRITER_CLASS_NAME = "org.apache.nifi.documentation.xml.XmlDocumentationWriter";
     private static final String CONNECTOR_DOCUMENTATION_WRITER_CLASS_NAME = "org.apache.nifi.documentation.xml.XmlConnectorDocumentationWriter";
 
+    static final Pattern VALID_MANIFEST_KEY_PATTERN = Pattern.compile("[A-Za-z0-9_-]+");
+
     private static final String[] DEFAULT_EXCLUDES = new String[]{"**/package.html"};
     private static final String[] DEFAULT_INCLUDES = new String[]{"**/**"};
 
@@ -477,6 +480,13 @@ public class NarMojo extends AbstractMojo {
     @Parameter(property = "skipDocGeneration", defaultValue = "false")
     protected boolean skipDocGeneration;
 
+    /**
+     * Additional key/value pairs to include in the NAR manifest.
+     * Keys must match the JAR manifest attribute name specification: {@code [A-Za-z0-9_-]+}.
+     */
+    @Parameter(property = "manifestEntries")
+    protected Map<String, String> manifestEntries;
+
     /**
      * The {@link RepositorySystemSession} used for obtaining the local and remote artifact repositories.
      */
@@ -1266,6 +1276,13 @@ private NarResult createArchive() throws MojoExecutionException {
 
             archive.addManifestEntry("Clone-During-Instance-Class-Loading", String.valueOf(cloneDuringInstanceClassLoading));
 
+            if (manifestEntries != null) {
+                validateManifestEntryKeys(manifestEntries);
+                for (final Map.Entry<String, String> entry : manifestEntries.entrySet()) {
+                    archive.addManifestEntry(entry.getKey(), entry.getValue());
+                }
+            }
+
             archiver.createArchive(session, project, archive);
             return new NarResult(narFile, extensionDocsFile);
         } catch (ArchiverException | MojoExecutionException | ManifestException | IOException | DependencyResolutionRequiredException e) {
@@ -1273,6 +1290,18 @@ private NarResult createArchive() throws MojoExecutionException {
         }
     }
 
+    static void validateManifestEntryKeys(final Map<String, String> entries) throws MojoExecutionException {
+        for (final String key : entries.keySet()) {
+            if (key == null || key.isEmpty()) {
+                throw new MojoExecutionException("Manifest entry key must not be null or empty");
+            }
+            if (!VALID_MANIFEST_KEY_PATTERN.matcher(key).matches()) {
+                throw new MojoExecutionException(
+                        "Manifest entry key '%s' contains invalid characters. Keys must match [A-Za-z0-9_-]+".formatted(key));
+            }
+        }
+    }
+
     private boolean notEmpty(String value) {
         return value != null && !value.isEmpty();
     }
diff --git a/src/test/java/org/apache/nifi/NarMojoTest.java b/src/test/java/org/apache/nifi/NarMojoTest.java
new file mode 100644
index 0000000..1d20a7f
--- /dev/null
+++ b/src/test/java/org/apache/nifi/NarMojoTest.java
@@ -0,0 +1,87 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.nifi;
+
+import org.apache.maven.plugin.MojoExecutionException;
+import org.junit.jupiter.api.Test;
+
+import java.util.HashMap;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+class NarMojoTest {
+
+    @Test
+    void testValidateManifestEntryKeysAcceptsValidKeys() throws MojoExecutionException {
+        final Map<String, String> entries = new LinkedHashMap<>();
+        entries.put("vendor", "Acme Corp");
+        entries.put("support-url", "https://acme.corp/support");
+        entries.put("build_number", "42");
+        entries.put("Tier-1", "gold");
+        entries.put("ABC123", "test");
+
+        NarMojo.validateManifestEntryKeys(entries);
+    }
+
+    @Test
+    void testValidateManifestEntryKeysRejectsEmptyKey() {
+        final Map<String, String> entries = new HashMap<>();
+        entries.put("", "some-value");
+
+        final MojoExecutionException exception = assertThrows(MojoExecutionException.class,
+                () -> NarMojo.validateManifestEntryKeys(entries));
+        assertEquals("Manifest entry key must not be null or empty", exception.getMessage());
+    }
+
+    @Test
+    void testValidateManifestEntryKeysRejectsKeyWithSpaces() {
+        final Map<String, String> entries = new HashMap<>();
+        entries.put("my key", "value");
+
+        final MojoExecutionException exception = assertThrows(MojoExecutionException.class,
+                () -> NarMojo.validateManifestEntryKeys(entries));
+        assertEquals("Manifest entry key 'my key' contains invalid characters. Keys must match [A-Za-z0-9_-]+", exception.getMessage());
+    }
+
+    @Test
+    void testValidateManifestEntryKeysRejectsKeyWithColon() {
+        final Map<String, String> entries = new HashMap<>();
+        entries.put("key:name", "value");
+
+        final MojoExecutionException exception = assertThrows(MojoExecutionException.class,
+                () -> NarMojo.validateManifestEntryKeys(entries));
+        assertEquals("Manifest entry key 'key:name' contains invalid characters. Keys must match [A-Za-z0-9_-]+", exception.getMessage());
+    }
+
+    @Test
+    void testValidateManifestEntryKeysRejectsKeyWithDot() {
+        final Map<String, String> entries = new HashMap<>();
+        entries.put("key.name", "value");
+
+        final MojoExecutionException exception = assertThrows(MojoExecutionException.class,
+                () -> NarMojo.validateManifestEntryKeys(entries));
+        assertEquals("Manifest entry key 'key.name' contains invalid characters. Keys must match [A-Za-z0-9_-]+", exception.getMessage());
+    }
+
+    @Test
+    void testValidateManifestEntryKeysAcceptsEmptyMap() throws MojoExecutionException {
+        NarMojo.validateManifestEntryKeys(Map.of());
+    }
+}