diff --git a/csaf_2_1/mandatoryTests.js b/csaf_2_1/mandatoryTests.js
index 95c5c092..fab00600 100644
--- a/csaf_2_1/mandatoryTests.js
+++ b/csaf_2_1/mandatoryTests.js
@@ -38,6 +38,7 @@ export { mandatoryTest_6_1_1 } from './mandatoryTests/mandatoryTest_6_1_1.js'
 export { mandatoryTest_6_1_8 } from './mandatoryTests/mandatoryTest_6_1_8.js'
 export { mandatoryTest_6_1_11 } from './mandatoryTests/mandatoryTest_6_1_11.js'
 export { mandatoryTest_6_1_13 } from './mandatoryTests/mandatoryTest_6_1_13.js'
+export { mandatoryTest_6_1_27_15 } from './mandatoryTests/mandatoryTest_6_1_27_15.js'
 export { mandatoryTest_6_1_34 } from './mandatoryTests/mandatoryTest_6_1_34.js'
 export { mandatoryTest_6_1_35 } from './mandatoryTests/mandatoryTest_6_1_35.js'
 export { mandatoryTest_6_1_9 } from './mandatoryTests/mandatoryTest_6_1_9.js'
diff --git a/csaf_2_1/mandatoryTests/mandatoryTest_6_1_27_15.js b/csaf_2_1/mandatoryTests/mandatoryTest_6_1_27_15.js
new file mode 100644
index 00000000..3118de3d
--- /dev/null
+++ b/csaf_2_1/mandatoryTests/mandatoryTest_6_1_27_15.js
@@ -0,0 +1,65 @@
+import Ajv from 'ajv/dist/jtd.js'
+
+const ajv = new Ajv()
+
+/*
+  This is the jtd schema that needs to match the input document so that the
+  test is activated. If this schema doesn't match it normally means that the input
+  document does not validate against the csaf json schema or optional fields that
+  the test checks are not present.
+ */
+const inputSchema = /** @type {const} */ ({
+  additionalProperties: true,
+  properties: {
+    document: {
+      additionalProperties: true,
+      properties: {
+        category: {
+          type: 'string',
+        },
+      },
+    },
+  },
+  optionalProperties: {
+    product_tree: {
+      additionalProperties: true,
+      properties: {},
+    },
+  },
+})
+
+const validate = ajv.compile(inputSchema)
+
+/**
+ * This implements the mandatory test 6.1.27.15 of the CSAF 2.1 standard.
+ *
+ * @param {unknown} doc
+ */
+export function mandatoryTest_6_1_27_15(doc) {
+  /*
+    The `ctx` variable holds the state that is accumulated during the test ran and is
+    finally returned by the function.
+   */
+  const ctx = {
+    errors:
+      /** @type {Array<{ instancePath: string; message: string }>} */ ([]),
+    isValid: true,
+  }
+
+  if (
+    !validate(doc) ||
+    !['csaf_withdrawn', 'csaf_superseded'].includes(doc.document.category)
+  )
+    return ctx
+
+  if (doc.product_tree) {
+    ctx.isValid = false
+    ctx.errors.push({
+      instancePath: `/product_tree`,
+      message:
+        'the product_tree is not allowed in the specified document category',
+    })
+  }
+
+  return ctx
+}
diff --git a/tests/csaf_2_1/mandatoryTest_6_1_27_15.js b/tests/csaf_2_1/mandatoryTest_6_1_27_15.js
new file mode 100644
index 00000000..d9a50013
--- /dev/null
+++ b/tests/csaf_2_1/mandatoryTest_6_1_27_15.js
@@ -0,0 +1,26 @@
+import assert from 'node:assert/strict'
+import { mandatoryTest_6_1_27_15 } from '../../csaf_2_1/mandatoryTests/mandatoryTest_6_1_27_15.js'
+
+describe('mandatoryTest_6_1_27_15', function () {
+  it('only runs on documents matching the input schema', function () {
+    assert.equal(
+      mandatoryTest_6_1_27_15({
+        document: 'invalid json',
+        product_tree: [],
+      }).isValid,
+      true
+    )
+  })
+
+  it('only runs on csaf_withdrawn and csaf_superseded documents', function () {
+    assert.equal(
+      mandatoryTest_6_1_27_15({
+        document: {
+          category: 'unknown category',
+        },
+        product_tree: [],
+      }).isValid,
+      true
+    )
+  })
+})
diff --git a/tests/csaf_2_1/oasis.js b/tests/csaf_2_1/oasis.js
index 6fb44c13..721128bc 100644
--- a/tests/csaf_2_1/oasis.js
+++ b/tests/csaf_2_1/oasis.js
@@ -23,7 +23,6 @@ const excluded = [
   '6.1.27.12',
   '6.1.27.13',
   '6.1.27.14',
-  '6.1.27.15',
   '6.1.27.16',
   '6.1.27.17',
   '6.1.27.18',