diff --git a/src/server/action-bodies.ts b/src/server/action-bodies.ts
index cb1a16b..8fe488d 100644
--- a/src/server/action-bodies.ts
+++ b/src/server/action-bodies.ts
@@ -69,6 +69,15 @@ export async function switchToOrganizationBody(data: {
 
 export async function getOrganizationBody(organizationId: string): Promise<OrganizationInfo | null> {
   try {
+    // Authorization: only resolve the organization the caller is currently
+    // authenticated within. The WorkOS client uses the app's API key, which can
+    // read any organization in the environment, so without this check any caller
+    // could fetch arbitrary organizations by ID (authorization bypass / IDOR).
+    const auth = getRawAuthFromContext();
+    if (!auth.user || auth.claims?.org_id !== organizationId) {
+      return null;
+    }
+
     const { getWorkOS } = await import('@workos/authkit-session');
     const workos = getWorkOS();
     const org = await workos.organizations.getOrganization(organizationId);
diff --git a/src/server/actions.spec.ts b/src/server/actions.spec.ts
index a0e999f..22a80fb 100644
--- a/src/server/actions.spec.ts
+++ b/src/server/actions.spec.ts
@@ -294,7 +294,11 @@ describe('Actions', () => {
   });
 
   describe('getOrganizationAction', () => {
-    it('returns organization info on success', async () => {
+    it('returns organization info for the current session organization', async () => {
+      mockAuthContext = {
+        auth: () => ({ user: { id: 'user_123' }, claims: { org_id: 'org_123' } }),
+        request: new Request('http://test.local'),
+      };
       mockGetOrganization.mockResolvedValue({ id: 'org_123', name: 'Test Org' });
 
       const result = await getOrganizationAction({ data: 'org_123' });
@@ -303,7 +307,35 @@ describe('Actions', () => {
       expect(result).toEqual({ id: 'org_123', name: 'Test Org' });
     });
 
+    it('denies fetching an organization the caller is not authenticated within', async () => {
+      // Session is scoped to org_123; the caller requests a different org.
+      mockAuthContext = {
+        auth: () => ({ user: { id: 'user_123' }, claims: { org_id: 'org_123' } }),
+        request: new Request('http://test.local'),
+      };
+      mockGetOrganization.mockResolvedValue({ id: 'org_456', name: 'Victim Org' });
+
+      const result = await getOrganizationAction({ data: 'org_456' });
+
+      expect(result).toBeNull();
+      expect(mockGetOrganization).not.toHaveBeenCalled();
+    });
+
+    it('returns null when there is no authenticated session', async () => {
+      mockAuthContext = null;
+      mockGetOrganization.mockResolvedValue({ id: 'org_123', name: 'Test Org' });
+
+      const result = await getOrganizationAction({ data: 'org_123' });
+
+      expect(result).toBeNull();
+      expect(mockGetOrganization).not.toHaveBeenCalled();
+    });
+
     it('returns null when organization is not found', async () => {
+      mockAuthContext = {
+        auth: () => ({ user: { id: 'user_123' }, claims: { org_id: 'bad_org' } }),
+        request: new Request('http://test.local'),
+      };
       mockGetOrganization.mockRejectedValue(new Error('Not found'));
 
       const result = await getOrganizationAction({ data: 'bad_org' });