diff --git a/modules/jarvos-gbrain/src/index.js b/modules/jarvos-gbrain/src/index.js
index cdc65d42..445eadd3 100644
--- a/modules/jarvos-gbrain/src/index.js
+++ b/modules/jarvos-gbrain/src/index.js
@@ -209,8 +209,23 @@ function resolveSourcePath(item, config) {
   const sourcePath = firstString(item.sourcePath, item.path);
   if (!sourcePath) return null;
   const expanded = expandTilde(sourcePath);
-  if (path.isAbsolute(expanded)) return expanded;
-  return path.join(config.vaultDir, expanded);
+  const vaultDir = path.resolve(config.vaultDir);
+  const resolved = path.resolve(vaultDir, expanded);
+  const relative = path.relative(vaultDir, resolved);
+  if (relative === '..' || relative.startsWith(`..${path.sep}`) || path.isAbsolute(relative)) return null;
+  return resolved;
+}
+
+function resolveRealSourcePath(sourcePath, config) {
+  try {
+    const vaultDir = fs.realpathSync(config.vaultDir);
+    const resolved = fs.realpathSync(sourcePath);
+    const relative = path.relative(vaultDir, resolved);
+    if (relative === '..' || relative.startsWith(`..${path.sep}`) || path.isAbsolute(relative)) return null;
+    return resolved;
+  } catch {
+    return null;
+  }
 }
 
 function targetPathForItem(item, config) {
@@ -354,20 +369,25 @@ function createImportPlan(overrides = {}) {
 
     const sourcePath = resolveSourcePath(item, config);
     if (!sourcePath) {
-      warnings.push(`Item ${index} is missing sourcePath`);
+      warnings.push(`Item ${index} has a missing or out-of-vault sourcePath`);
       continue;
     }
     if (!fs.existsSync(sourcePath)) {
       warnings.push(`Item ${index} source does not exist: ${sourcePath}`);
       continue;
     }
+    const realSourcePath = resolveRealSourcePath(sourcePath, config);
+    if (!realSourcePath) {
+      warnings.push(`Item ${index} source is outside the vault: ${sourcePath}`);
+      continue;
+    }
 
     const targetPath = targetPathForItem(item, config);
     items.push({
       index,
       type: pageType,
       title: firstString(item.title, path.basename(sourcePath, '.md')),
-      sourcePath,
+      sourcePath: realSourcePath,
       targetPath,
       slug: path.basename(targetPath, '.md'),
       tags: Array.isArray(item.tags) ? item.tags : [],
diff --git a/modules/jarvos-gbrain/test/gbrain.test.js b/modules/jarvos-gbrain/test/gbrain.test.js
index 8f8e342f..c33a499b 100644
--- a/modules/jarvos-gbrain/test/gbrain.test.js
+++ b/modules/jarvos-gbrain/test/gbrain.test.js
@@ -157,6 +157,51 @@ test('createImportPlan maps curated manifest items to GBrain targets', () => {
   assert.equal(plan.warnings.length, 1);
 });
 
+test('createImportPlan rejects source paths outside the configured vault', () => {
+  const root = tempDir();
+  const vault = path.join(root, 'vault');
+  const brain = path.join(root, 'brain');
+  const outsideNote = path.join(root, 'secret.md');
+  const manifestPath = path.join(root, 'manifest.json');
+
+  fs.mkdirSync(vault, { recursive: true });
+  fs.writeFileSync(outsideNote, 'must not be imported', 'utf8');
+  fs.writeFileSync(manifestPath, JSON.stringify({
+    version: 1,
+    items: [
+      { type: 'source', sourcePath: '../secret.md' },
+      { type: 'source', sourcePath: outsideNote },
+    ],
+  }), 'utf8');
+
+  const plan = gbrain.createImportPlan({ vaultDir: vault, brainDir: brain, manifestPath });
+
+  assert.equal(plan.itemCount, 0);
+  assert.equal(plan.warnings.length, 2);
+  assert.ok(plan.warnings.every((warning) => /out-of-vault/.test(warning)));
+});
+
+test('createImportPlan rejects symlinks that escape the configured vault', () => {
+  const root = tempDir();
+  const vault = path.join(root, 'vault');
+  const outsideNote = path.join(root, 'secret.md');
+  const link = path.join(vault, 'linked-secret.md');
+  const manifestPath = path.join(root, 'manifest.json');
+
+  fs.mkdirSync(vault, { recursive: true });
+  fs.writeFileSync(outsideNote, 'must not be imported', 'utf8');
+  fs.symlinkSync(outsideNote, link);
+  fs.writeFileSync(manifestPath, JSON.stringify({
+    version: 1,
+    items: [{ type: 'source', sourcePath: 'linked-secret.md' }],
+  }), 'utf8');
+
+  const plan = gbrain.createImportPlan({ vaultDir: vault, manifestPath });
+
+  assert.equal(plan.itemCount, 0);
+  assert.match(plan.warnings[0], /outside the vault/);
+});
+
 test('importToBrain dry-run does not write generated pages', () => {
   const root = tempDir();
   const vault = path.join(root, 'vault');