diff --git a/etl-service/src/test/java/com/xtrmetl/etl/documentation/JacksonSecurityBaselineTest.java b/etl-service/src/test/java/com/xtrmetl/etl/documentation/JacksonSecurityBaselineTest.java
new file mode 100644
index 00000000..582c3c18
--- /dev/null
+++ b/etl-service/src/test/java/com/xtrmetl/etl/documentation/JacksonSecurityBaselineTest.java
@@ -0,0 +1,163 @@
+package com.xtrmetl.etl.documentation;
+
+import org.junit.jupiter.api.Test;
+import org.w3c.dom.Element;
+import org.w3c.dom.Node;
+import org.xml.sax.InputSource;
+
+import javax.xml.XMLConstants;
+import javax.xml.parsers.DocumentBuilderFactory;
+import java.io.IOException;
+import java.io.StringReader;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+/**
+ * Guards the shared Maven dependency-management boundary against Jackson Databind versions below
+ * the selected patched 2.21.5 security baseline.
+ */
+class JacksonSecurityBaselineTest {
+
+    private static final Path PROJECT_ROOT = projectRoot();
+
+    @Test
+    void jacksonSecurityBomPrecedesImportedSpringBootDependencyManagement() throws IOException {
+        String pom = Files.readString(PROJECT_ROOT.resolve("pom.xml"), StandardCharsets.UTF_8);
+
+        assertJacksonBomContract(pom);
+    }
+
+    @Test
+    void rejectsJacksonBomDecoysOutsideRootDependencyManagement() {
+        String pomWithDecoy = """
+                <project>
+                  <properties>
+                    <jackson-bom.version>2.21.5</jackson-bom.version>
+                  </properties>
+                  <!-- <artifactId>jackson-bom</artifactId> -->
+                  <dependencyManagement>
+                    <dependencies>
+                      <dependency>
+                        <artifactId>spring-boot-dependencies</artifactId>
+                      </dependency>
+                    </dependencies>
+                  </dependencyManagement>
+                </project>
+                """;
+
+        assertThrows(AssertionError.class, () -> assertJacksonBomContract(pomWithDecoy));
+    }
+
+    private static void assertJacksonBomContract(String pom) {
+        Element project = parseProject(pom);
+        Element properties = requireDirectChild(project, "properties");
+        assertEquals(
+                "2.21.5",
+                requireDirectChild(properties, "jackson-bom.version").getTextContent().trim(),
+                "Root properties must pin Jackson 2.21.5, the current patched 2.21 LTS baseline"
+        );
+
+        Element dependencyManagement = requireDirectChild(project, "dependencyManagement");
+        Element dependencies = requireDirectChild(dependencyManagement, "dependencies");
+        List<Element> managedDependencies = directChildren(dependencies, "dependency");
+
+        int jacksonIndex = -1;
+        int springBootIndex = -1;
+        int jacksonCount = 0;
+        for (int index = 0; index < managedDependencies.size(); index++) {
+            Element dependency = managedDependencies.get(index);
+            String artifactId = directChildText(dependency, "artifactId");
+            if ("jackson-bom".equals(artifactId)) {
+                jacksonCount++;
+                jacksonIndex = index;
+                assertEquals("com.fasterxml.jackson", directChildText(dependency, "groupId"));
+                assertEquals("${jackson-bom.version}", directChildText(dependency, "version"));
+                assertEquals("pom", directChildText(dependency, "type"));
+                assertEquals("import", directChildText(dependency, "scope"));
+            }
+            if ("spring-boot-dependencies".equals(artifactId)) {
+                assertEquals("org.springframework.boot", directChildText(dependency, "groupId"));
+                springBootIndex = index;
+            }
+        }
+
+        assertEquals(1, jacksonCount, "Root dependencyManagement must import exactly one Jackson BOM");
+        assertTrue(springBootIndex >= 0, "Root dependencyManagement must continue importing Spring Boot dependencies");
+        assertTrue(
+                jacksonIndex < springBootIndex,
+                "Without the Spring Boot parent POM, the explicit Jackson override BOM must precede spring-boot-dependencies"
+        );
+    }
+
+    private static Element parseProject(String pom) {
+        try {
+            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
+            factory.setNamespaceAware(true);
+            factory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
+            factory.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
+            factory.setFeature("http://xml.org/sax/features/external-general-entities", false);
+            factory.setFeature("http://xml.org/sax/features/external-parameter-entities", false);
+            factory.setXIncludeAware(false);
+            factory.setExpandEntityReferences(false);
+            return factory.newDocumentBuilder()
+                    .parse(new InputSource(new StringReader(pom)))
+                    .getDocumentElement();
+        } catch (Exception exception) {
+            throw new AssertionError("Root pom.xml must be parseable XML for structural dependency validation", exception);
+        }
+    }
+
+    private static Element requireDirectChild(Element parent, String name) {
+        for (Node child = parent.getFirstChild(); child != null; child = child.getNextSibling()) {
+            if (child instanceof Element element && name.equals(elementName(element))) {
+                return element;
+            }
+        }
+        throw new AssertionError("Missing direct <" + name + "> under <" + elementName(parent) + ">");
+    }
+
+    private static List<Element> directChildren(Element parent, String name) {
+        List<Element> children = new ArrayList<>();
+        for (Node child = parent.getFirstChild(); child != null; child = child.getNextSibling()) {
+            if (child instanceof Element element && name.equals(elementName(element))) {
+                children.add(element);
+            }
+        }
+        return children;
+    }
+
+    private static String directChildText(Element parent, String name) {
+        return requireDirectChild(parent, name).getTextContent().trim();
+    }
+
+    private static String elementName(Node node) {
+        return node.getLocalName() == null ? node.getNodeName() : node.getLocalName();
+    }
+
+    /** Finds the repository root from root- or module-scoped Maven execution. */
+    private static Path projectRoot() {
+        Path current = Paths.get(System.getProperty("user.dir")).toAbsolutePath();
+        Path lastPomParent = null;
+        while (current != null) {
+            if (Files.exists(current.resolve(".git"))) {
+                return current;
+            }
+            if (Files.exists(current.resolve("pom.xml"))) {
+                lastPomParent = current;
+            }
+            current = current.getParent();
+        }
+        if (lastPomParent != null) {
+            return lastPomParent;
+        }
+        throw new IllegalStateException("Could not find project root");
+    }
+}
diff --git a/pom.xml b/pom.xml
index 7c0ee7c2..c5c46ae4 100644
--- a/pom.xml
+++ b/pom.xml
@@ -23,6 +23,7 @@
         <java.version>25</java.version>
         <spring-boot.version>3.5.16</spring-boot.version>
         <spring-cloud.version>2025.0.3</spring-cloud.version>
+        <jackson-bom.version>2.21.5</jackson-bom.version>
         <postgresql.version>42.7.12</postgresql.version>
         <spring-kafka.version>3.3.16</spring-kafka.version>
         <spring-retry.version>2.0.13</spring-retry.version>
@@ -33,6 +34,13 @@
 
     <dependencyManagement>
         <dependencies>
+            <dependency>
+                <groupId>com.fasterxml.jackson</groupId>
+                <artifactId>jackson-bom</artifactId>
+                <version>${jackson-bom.version}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
             <dependency>
                 <groupId>org.springframework.boot</groupId>
                 <artifactId>spring-boot-dependencies</artifactId>