diff --git a/apps/pom.xml b/apps/pom.xml
index 09a2ddf38..87a022ae1 100644
--- a/apps/pom.xml
+++ b/apps/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-parent</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
     <artifactId>struts2-apps</artifactId>
     <packaging>pom</packaging>
diff --git a/apps/rest-showcase/pom.xml b/apps/rest-showcase/pom.xml
index 7f31e545d..3a2553609 100644
--- a/apps/rest-showcase/pom.xml
+++ b/apps/rest-showcase/pom.xml
@@ -24,12 +24,12 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-apps</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-rest-showcase</artifactId>
     <packaging>war</packaging>
-    <version>2.5.27</version>
+    <version>2.5.28-SNAPSHOT</version>
     <name>Struts 2 Rest Showcase Webapp</name>
     <description>Struts 2 Rest Showcase Example</description>
 
diff --git a/apps/showcase/pom.xml b/apps/showcase/pom.xml
index 39ecdd9a2..ab94e0385 100644
--- a/apps/showcase/pom.xml
+++ b/apps/showcase/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-apps</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-showcase</artifactId>
diff --git a/assembly/pom.xml b/assembly/pom.xml
index 68588e3b6..cfa32445d 100644
--- a/assembly/pom.xml
+++ b/assembly/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-parent</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-assembly</artifactId>
diff --git a/bom/pom.xml b/bom/pom.xml
index 2b76a2c78..6cc120230 100644
--- a/bom/pom.xml
+++ b/bom/pom.xml
@@ -30,7 +30,7 @@
     </parent>
 
     <artifactId>struts2-bom</artifactId>
-    <version>2.5.27</version>
+    <version>2.5.28-SNAPSHOT</version>
     <packaging>pom</packaging>
 
     <name>Struts 2 Bill of Materials</name>
@@ -45,7 +45,7 @@
     </licenses>
 
     <properties>
-        <struts-version.version>2.5.27</struts-version.version>
+        <struts-version.version>2.5.28-SNAPSHOT</struts-version.version>
         <maven.site.skip>true</maven.site.skip>
         <maven.site.deploy.skip>true</maven.site.deploy.skip>
     </properties>
diff --git a/bundles/admin/pom.xml b/bundles/admin/pom.xml
index 28b96e81c..7a954b119 100644
--- a/bundles/admin/pom.xml
+++ b/bundles/admin/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-osgi-bundles</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-osgi-admin-bundle</artifactId>
diff --git a/bundles/demo/pom.xml b/bundles/demo/pom.xml
index 5a379eb8f..346323fa5 100644
--- a/bundles/demo/pom.xml
+++ b/bundles/demo/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-osgi-bundles</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-osgi-demo-bundle</artifactId>
diff --git a/bundles/pom.xml b/bundles/pom.xml
index 99b06681f..f54b6aa0b 100755
--- a/bundles/pom.xml
+++ b/bundles/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-parent</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-osgi-bundles</artifactId>
diff --git a/core/pom.xml b/core/pom.xml
index bdeb2dd98..594196ba2 100644
--- a/core/pom.xml
+++ b/core/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-parent</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
     <artifactId>struts2-core</artifactId>
     <packaging>jar</packaging>
diff --git a/plugins/bean-validation/pom.xml b/plugins/bean-validation/pom.xml
index 80bd97396..b84639572 100644
--- a/plugins/bean-validation/pom.xml
+++ b/plugins/bean-validation/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
     <modelVersion>4.0.0</modelVersion>
 
diff --git a/plugins/cdi/pom.xml b/plugins/cdi/pom.xml
index 4dcd2db82..549202ea6 100644
--- a/plugins/cdi/pom.xml
+++ b/plugins/cdi/pom.xml
@@ -25,7 +25,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-cdi-plugin</artifactId>
diff --git a/plugins/config-browser/pom.xml b/plugins/config-browser/pom.xml
index 71877c8f4..9ec03a0a2 100644
--- a/plugins/config-browser/pom.xml
+++ b/plugins/config-browser/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-config-browser-plugin</artifactId>
diff --git a/plugins/convention/pom.xml b/plugins/convention/pom.xml
index 06a62cbed..70a67ec85 100644
--- a/plugins/convention/pom.xml
+++ b/plugins/convention/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-convention-plugin</artifactId>
diff --git a/plugins/dwr/pom.xml b/plugins/dwr/pom.xml
index 29f7e3e3f..e3faa556d 100644
--- a/plugins/dwr/pom.xml
+++ b/plugins/dwr/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-dwr-plugin</artifactId>
diff --git a/plugins/embeddedjsp/pom.xml b/plugins/embeddedjsp/pom.xml
index da001ba8a..1301a914d 100644
--- a/plugins/embeddedjsp/pom.xml
+++ b/plugins/embeddedjsp/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-embeddedjsp-plugin</artifactId>
diff --git a/plugins/gxp/pom.xml b/plugins/gxp/pom.xml
index 7fb7c3f83..81ce9e89c 100644
--- a/plugins/gxp/pom.xml
+++ b/plugins/gxp/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-gxp-plugin</artifactId>
diff --git a/plugins/jasperreports/pom.xml b/plugins/jasperreports/pom.xml
index b7dc92351..9136aeb1b 100644
--- a/plugins/jasperreports/pom.xml
+++ b/plugins/jasperreports/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-jasperreports-plugin</artifactId>
diff --git a/plugins/javatemplates/pom.xml b/plugins/javatemplates/pom.xml
index 913bee8d9..a481565ed 100644
--- a/plugins/javatemplates/pom.xml
+++ b/plugins/javatemplates/pom.xml
@@ -25,7 +25,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-javatemplates-plugin</artifactId>
diff --git a/plugins/jfreechart/pom.xml b/plugins/jfreechart/pom.xml
index 7a1427abc..6171fed10 100644
--- a/plugins/jfreechart/pom.xml
+++ b/plugins/jfreechart/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
    </parent>
 
     <artifactId>struts2-jfreechart-plugin</artifactId>
diff --git a/plugins/json/pom.xml b/plugins/json/pom.xml
index 2f840cd02..e3d96c424 100644
--- a/plugins/json/pom.xml
+++ b/plugins/json/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-json-plugin</artifactId>
diff --git a/plugins/junit/pom.xml b/plugins/junit/pom.xml
index 4dc8ac4fb..6e1001440 100644
--- a/plugins/junit/pom.xml
+++ b/plugins/junit/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-junit-plugin</artifactId>
diff --git a/plugins/osgi/pom.xml b/plugins/osgi/pom.xml
index 8409eb771..786f649e6 100644
--- a/plugins/osgi/pom.xml
+++ b/plugins/osgi/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-osgi-plugin</artifactId>
diff --git a/plugins/oval/pom.xml b/plugins/oval/pom.xml
index 5ee817606..14b306f16 100644
--- a/plugins/oval/pom.xml
+++ b/plugins/oval/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-oval-plugin</artifactId>
diff --git a/plugins/pell-multipart/pom.xml b/plugins/pell-multipart/pom.xml
index 08cacc654..ffeac020e 100644
--- a/plugins/pell-multipart/pom.xml
+++ b/plugins/pell-multipart/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-pell-multipart-plugin</artifactId>
diff --git a/plugins/plexus/pom.xml b/plugins/plexus/pom.xml
index 6733342ba..59876d37d 100644
--- a/plugins/plexus/pom.xml
+++ b/plugins/plexus/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-plexus-plugin</artifactId>
diff --git a/plugins/pom.xml b/plugins/pom.xml
index f1d5f481d..883731e51 100644
--- a/plugins/pom.xml
+++ b/plugins/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-parent</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-plugins</artifactId>
diff --git a/plugins/portlet-tiles/pom.xml b/plugins/portlet-tiles/pom.xml
index cb5ad6ba1..72bc91f63 100644
--- a/plugins/portlet-tiles/pom.xml
+++ b/plugins/portlet-tiles/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-portlet-tiles-plugin</artifactId>
diff --git a/plugins/portlet/pom.xml b/plugins/portlet/pom.xml
index 89d3f44e5..f46b5ef77 100644
--- a/plugins/portlet/pom.xml
+++ b/plugins/portlet/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-portlet-plugin</artifactId>
diff --git a/plugins/rest/pom.xml b/plugins/rest/pom.xml
index 5add6fd74..f373a9090 100644
--- a/plugins/rest/pom.xml
+++ b/plugins/rest/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-rest-plugin</artifactId>
diff --git a/plugins/sitegraph/pom.xml b/plugins/sitegraph/pom.xml
index 6141a6bad..824c6b598 100644
--- a/plugins/sitegraph/pom.xml
+++ b/plugins/sitegraph/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-sitegraph-plugin</artifactId>
diff --git a/plugins/sitemesh/pom.xml b/plugins/sitemesh/pom.xml
index d90884027..7274687c2 100644
--- a/plugins/sitemesh/pom.xml
+++ b/plugins/sitemesh/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-sitemesh-plugin</artifactId>
diff --git a/plugins/spring/pom.xml b/plugins/spring/pom.xml
index 322cbfffa..c12747add 100644
--- a/plugins/spring/pom.xml
+++ b/plugins/spring/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-spring-plugin</artifactId>
diff --git a/plugins/testng/pom.xml b/plugins/testng/pom.xml
index 9d765c89e..53601b9cf 100644
--- a/plugins/testng/pom.xml
+++ b/plugins/testng/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-testng-plugin</artifactId>
diff --git a/plugins/tiles/pom.xml b/plugins/tiles/pom.xml
index 42f2ac8bb..f3992b1ac 100644
--- a/plugins/tiles/pom.xml
+++ b/plugins/tiles/pom.xml
@@ -24,7 +24,7 @@
     <parent>
         <groupId>org.apache.struts</groupId>
         <artifactId>struts2-plugins</artifactId>
-        <version>2.5.27</version>
+        <version>2.5.28-SNAPSHOT</version>
     </parent>
 
     <artifactId>struts2-tiles-plugin</artifactId>
diff --git a/pom.xml b/pom.xml
index 903fb5791..b68937f2b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -29,7 +29,7 @@
 
     <modelVersion>4.0.0</modelVersion>
     <artifactId>struts2-parent</artifactId>
-    <version>2.5.27</version>
+    <version>2.5.28-SNAPSHOT</version>
     <packaging>pom</packaging>
     <name>Struts 2</name>
     <url>http://struts.apache.org/</url>
@@ -96,7 +96,7 @@
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <project.build.outputTimestamp>2021-10-19T07:39:18Z</project.build.outputTimestamp>
+        <project.build.outputTimestamp>2021-10-19T07:54:25Z</project.build.outputTimestamp>
 
         <!-- Dependencies -->
         <ognl.version>3.1.29</ognl.version>