feat(authz): prevent non-owners from managing owner memberships

app/controlplane/internal/service/organization.go

@@ -19,6 +19,7 @@ import (
 	"context"
 
 	pb "github.com/chainloop-dev/chainloop/app/controlplane/api/controlplane/v1"
+	"github.com/chainloop-dev/chainloop/app/controlplane/internal/usercontext"
 	"github.com/chainloop-dev/chainloop/app/controlplane/internal/usercontext/entities"
 	"github.com/chainloop-dev/chainloop/app/controlplane/pkg/authz"
 	"github.com/chainloop-dev/chainloop/app/controlplane/pkg/biz"
@@ -196,7 +197,8 @@ func (s *OrganizationService) DeleteMembership(ctx context.Context, req *pb.Orga
 		return nil, err
 	}
 
-	if err := s.membershipUC.DeleteOther(ctx, currentOrg.ID, currentUser.ID, req.MembershipId); err != nil {
+	callerRole := authz.Role(usercontext.CurrentAuthzSubject(ctx))
+	if err := s.membershipUC.DeleteOther(ctx, currentOrg.ID, currentUser.ID, req.MembershipId, callerRole); err != nil {
 		return nil, handleUseCaseErr(err, s.log)
 	}
 
@@ -214,7 +216,8 @@ func (s *OrganizationService) UpdateMembership(ctx context.Context, req *pb.Orga
 		return nil, err
 	}
 
-	m, err := s.membershipUC.UpdateRole(ctx, currentOrg.ID, currentUser.ID, req.MembershipId, biz.PbRoleToBiz(req.Role))
+	callerRole := authz.Role(usercontext.CurrentAuthzSubject(ctx))
+	m, err := s.membershipUC.UpdateRole(ctx, currentOrg.ID, currentUser.ID, req.MembershipId, biz.PbRoleToBiz(req.Role), callerRole)
 	if err != nil {
 		return nil, handleUseCaseErr(err, s.log)
 	}

app/controlplane/pkg/authz/authz.go

@@ -1,5 +1,5 @@
 //
-// Copyright 2024-2025 The Chainloop Authors.
+// Copyright 2024-2026 The Chainloop Authors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -36,11 +36,12 @@ func (r Role) IsAdmin() bool {
 const (
 	// Actions
 
-	ActionRead   = "read"
-	ActionList   = "list"
-	ActionCreate = "create"
-	ActionUpdate = "update"
-	ActionDelete = "delete"
+	ActionRead         = "read"
+	ActionList         = "list"
+	ActionCreate       = "create"
+	ActionUpdate       = "update"
+	ActionDelete       = "delete"
+	ActionManageOwners = "manage_owners"
 
 	// Resources
 
@@ -175,6 +176,9 @@ var (
 	PolicyProjectRemoveMemberships = &Policy{ResourceProjectMembership, ActionDelete}
 	// Organization Invitations
 	PolicyOrganizationInvitationsCreate = &Policy{ResourceOrganizationInvitations, ActionCreate}
+
+	// Manage owners (promote to/demote from owner, remove owners)
+	PolicyOrganizationManageOwners = &Policy{OrganizationMemberships, ActionManageOwners}
 )
 
 // RolesMap The default list of policies for each role
@@ -193,6 +197,7 @@ var RolesMap = map[Role][]*Policy{
 	},
 	RoleOwner: {
 		PolicyOrganizationDelete,
+		PolicyOrganizationManageOwners,
 	},
 	// RoleAdmin is an org-scoped role that provides super admin privileges (it's the higher role)
 	RoleAdmin: {

app/controlplane/pkg/biz/membership.go

@@ -1,5 +1,5 @@
 //
-// Copyright 2024-2025 The Chainloop Authors.
+// Copyright 2024-2026 The Chainloop Authors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -90,15 +90,17 @@ type MembershipUseCase struct {
 	// Use Cases
 	orgUseCase *OrganizationUseCase
 	auditor    *AuditorUseCase
+	authzUC    *AuthzUseCase
 }
 
-func NewMembershipUseCase(repo MembershipRepo, orgUC *OrganizationUseCase, auditor *AuditorUseCase, userRepo UserRepo, logger log.Logger) *MembershipUseCase {
-	return &MembershipUseCase{repo: repo, orgUseCase: orgUC, logger: log.NewHelper(logger), userRepo: userRepo, auditor: auditor}
+func NewMembershipUseCase(repo MembershipRepo, orgUC *OrganizationUseCase, auditor *AuditorUseCase, userRepo UserRepo, authzUC *AuthzUseCase, logger log.Logger) *MembershipUseCase {
+	return &MembershipUseCase{repo: repo, orgUseCase: orgUC, logger: log.NewHelper(logger), userRepo: userRepo, auditor: auditor, authzUC: authzUC}
 }
 
 // DeleteOther just deletes a membership from the database
-// but ensures that the user is not deleting itself from the org
-func (uc *MembershipUseCase) DeleteOther(ctx context.Context, orgID, userID, membershipID string) error {
+// but ensures that the user is not deleting itself from the org.
+// callerRole is the authorization subject of the caller (e.g. their org role).
+func (uc *MembershipUseCase) DeleteOther(ctx context.Context, orgID, userID, membershipID string, callerRole authz.Role) error {
 	membershipUUID, err := uuid.Parse(membershipID)
 	if err != nil {
 		return NewErrInvalidUUID(err)
@@ -120,6 +122,13 @@ func (uc *MembershipUseCase) DeleteOther(ctx context.Context, orgID, userID, mem
 		return NewErrValidationStr("cannot delete yourself from the org")
 	}
 
+	// Only owners can remove other owners
+	if m.Role == authz.RoleOwner {
+		if err := uc.enforceManageOwners(ctx, callerRole); err != nil {
+			return err
+		}
+	}
+
 	uc.logger.Infow("msg", "Deleting membership", "org_id", orgID, "membership_id", m.ID.String())
 
 	// Delete the main membership - this will also remove the user from all groups in the org
@@ -131,7 +140,7 @@ func (uc *MembershipUseCase) DeleteOther(ctx context.Context, orgID, userID, mem
 	return nil
 }
 
-func (uc *MembershipUseCase) UpdateRole(ctx context.Context, orgID, userID, membershipID string, role authz.Role) (*Membership, error) {
+func (uc *MembershipUseCase) UpdateRole(ctx context.Context, orgID, userID, membershipID string, role authz.Role, callerRole authz.Role) (*Membership, error) {
 	// If it has ben overrode by the user, validate it
 	if role == "" {
 		return nil, NewErrValidationStr("role is required")
@@ -160,6 +169,13 @@ func (uc *MembershipUseCase) UpdateRole(ctx context.Context, orgID, userID, memb
 		return nil, NewErrValidationStr("cannot update yourself")
 	}
 
+	// Only owners can modify owner memberships or promote users to owner
+	if m.Role == authz.RoleOwner || role == authz.RoleOwner {
+		if err := uc.enforceManageOwners(ctx, callerRole); err != nil {
+			return nil, err
+		}
+	}
+
 	userUUID, err := uuid.Parse(m.User.ID)
 	if err != nil {
 		return nil, NewErrInvalidUUID(err)
@@ -187,6 +203,20 @@ func (uc *MembershipUseCase) UpdateRole(ctx context.Context, orgID, userID, memb
 	return updatedMembership, nil
 }
 
+// enforceManageOwners checks that the caller has the manage_owners policy.
+func (uc *MembershipUseCase) enforceManageOwners(ctx context.Context, callerRole authz.Role) error {
+	ok, err := uc.authzUC.Enforce(ctx, string(callerRole), authz.PolicyOrganizationManageOwners)
+	if err != nil {
+		return fmt.Errorf("failed to enforce manage owners policy: %w", err)
+	}
+
+	if !ok {
+		return NewErrUnauthorizedStr("only organization owners can manage owner memberships")
+	}
+
+	return nil
+}
+
 type membershipCreateOpts struct {
 	current bool
 	role    authz.Role

app/controlplane/pkg/biz/membership_integration_test.go

@@ -1,5 +1,5 @@
 //
-// Copyright 2024-2025 The Chainloop Authors.
+// Copyright 2024-2026 The Chainloop Authors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -229,12 +229,12 @@ func (s *membershipIntegrationTestSuite) TestDeleteOther() {
 	s.NoError(err)
 
 	s.T().Run("I can not delete my own membership", func(t *testing.T) {
-		err := s.Membership.DeleteOther(ctx, sharedOrg.ID, user2.ID, mUser2SharedOrg.ID.String())
+		err := s.Membership.DeleteOther(ctx, sharedOrg.ID, user2.ID, mUser2SharedOrg.ID.String(), authz.RoleOwner)
 		s.ErrorContains(err, "cannot delete yourself from the org")
 	})
 
 	s.T().Run("I can't find the membership", func(t *testing.T) {
-		err := s.Membership.DeleteOther(ctx, otherOrg.ID, user2.ID, mUser2SharedOrg.ID.String())
+		err := s.Membership.DeleteOther(ctx, otherOrg.ID, user2.ID, mUser2SharedOrg.ID.String(), authz.RoleOwner)
 		s.True(biz.IsNotFound(err))
 	})
 
@@ -244,7 +244,7 @@ func (s *membershipIntegrationTestSuite) TestDeleteOther() {
 		s.Len(memberships, 1)
 		s.Equal(1, count)
 
-		err = s.Membership.DeleteOther(ctx, sharedOrg.ID, user.ID, mUser2SharedOrg.ID.String())
+		err = s.Membership.DeleteOther(ctx, sharedOrg.ID, user.ID, mUser2SharedOrg.ID.String(), authz.RoleOwner)
 		s.NoError(err)
 
 		memberships, count, err = s.Membership.ByOrg(ctx, sharedOrg.ID, &biz.ListByOrgOpts{}, nil)
@@ -270,17 +270,17 @@ func (s *membershipIntegrationTestSuite) TestUpdateRole() {
 
 	// empty role
 	s.T().Run("a role is required", func(t *testing.T) {
-		_, err := s.Membership.UpdateRole(ctx, sharedOrg.ID, user.ID, mUser2SharedOrg.ID.String(), "")
+		_, err := s.Membership.UpdateRole(ctx, sharedOrg.ID, user.ID, mUser2SharedOrg.ID.String(), "", authz.RoleOwner)
 		s.ErrorContains(err, "role is required")
 	})
 
 	s.T().Run("I can not update my own membership", func(t *testing.T) {
-		_, err := s.Membership.UpdateRole(ctx, sharedOrg.ID, user2.ID, mUser2SharedOrg.ID.String(), authz.RoleAdmin)
+		_, err := s.Membership.UpdateRole(ctx, sharedOrg.ID, user2.ID, mUser2SharedOrg.ID.String(), authz.RoleAdmin, authz.RoleOwner)
 		s.ErrorContains(err, "cannot update yourself")
 	})
 
 	s.T().Run("I can't find the membership in another org", func(t *testing.T) {
-		_, err := s.Membership.UpdateRole(ctx, otherOrg.ID, user.ID, mUser2SharedOrg.ID.String(), authz.RoleAdmin)
+		_, err := s.Membership.UpdateRole(ctx, otherOrg.ID, user.ID, mUser2SharedOrg.ID.String(), authz.RoleAdmin, authz.RoleOwner)
 		s.True(biz.IsNotFound(err))
 	})
 
@@ -291,12 +291,81 @@ func (s *membershipIntegrationTestSuite) TestUpdateRole() {
 		s.Equal(1, count)
 		s.Equal(authz.RoleViewer, memberships[0].Role)
 
-		got, err := s.Membership.UpdateRole(ctx, sharedOrg.ID, user.ID, mUser2SharedOrg.ID.String(), authz.RoleAdmin)
+		got, err := s.Membership.UpdateRole(ctx, sharedOrg.ID, user.ID, mUser2SharedOrg.ID.String(), authz.RoleAdmin, authz.RoleOwner)
 		s.NoError(err)
 		s.Equal(authz.RoleAdmin, got.Role)
 	})
 }
 
+func (s *membershipIntegrationTestSuite) TestOwnerGuards() {
+	ctx := context.Background()
+
+	owner, err := s.User.UpsertByEmail(ctx, "owner@test.com", nil)
+	s.NoError(err)
+	admin, err := s.User.UpsertByEmail(ctx, "admin@test.com", nil)
+	s.NoError(err)
+	target, err := s.User.UpsertByEmail(ctx, "target@test.com", nil)
+	s.NoError(err)
+
+	org, err := s.Organization.CreateWithRandomName(ctx)
+	s.NoError(err)
+
+	// owner is org owner, admin is org admin, target starts as viewer
+	_, err = s.Membership.Create(ctx, org.ID, owner.ID, biz.WithMembershipRole(authz.RoleOwner))
+	s.NoError(err)
+	_, err = s.Membership.Create(ctx, org.ID, admin.ID, biz.WithMembershipRole(authz.RoleAdmin))
+	s.NoError(err)
+	mTarget, err := s.Membership.Create(ctx, org.ID, target.ID, biz.WithMembershipRole(authz.RoleViewer))
+	s.NoError(err)
+
+	s.Run("admin cannot promote user to owner", func() {
+		_, err := s.Membership.UpdateRole(ctx, org.ID, admin.ID, mTarget.ID.String(), authz.RoleOwner, authz.RoleAdmin)
+		s.Error(err)
+		s.True(biz.IsErrUnauthorized(err))
+		s.Contains(err.Error(), "only organization owners can manage owner memberships")
+	})
+
+	s.Run("owner can promote user to owner", func() {
+		got, err := s.Membership.UpdateRole(ctx, org.ID, owner.ID, mTarget.ID.String(), authz.RoleOwner, authz.RoleOwner)
+		s.NoError(err)
+		s.Equal(authz.RoleOwner, got.Role)
+	})
+
+	s.Run("admin cannot demote an owner", func() {
+		_, err := s.Membership.UpdateRole(ctx, org.ID, admin.ID, mTarget.ID.String(), authz.RoleAdmin, authz.RoleAdmin)
+		s.Error(err)
+		s.True(biz.IsErrUnauthorized(err))
+		s.Contains(err.Error(), "only organization owners can manage owner memberships")
+	})
+
+	s.Run("owner can demote another owner", func() {
+		got, err := s.Membership.UpdateRole(ctx, org.ID, owner.ID, mTarget.ID.String(), authz.RoleAdmin, authz.RoleOwner)
+		s.NoError(err)
+		s.Equal(authz.RoleAdmin, got.Role)
+	})
+
+	s.Run("admin cannot delete an owner membership", func() {
+		// First promote target back to owner
+		_, err := s.Membership.UpdateRole(ctx, org.ID, owner.ID, mTarget.ID.String(), authz.RoleOwner, authz.RoleOwner)
+		s.NoError(err)
+
+		err = s.Membership.DeleteOther(ctx, org.ID, admin.ID, mTarget.ID.String(), authz.RoleAdmin)
+		s.Error(err)
+		s.True(biz.IsErrUnauthorized(err))
+		s.Contains(err.Error(), "only organization owners can manage owner memberships")
+	})
+
+	s.Run("owner can delete another owner membership", func() {
+		err := s.Membership.DeleteOther(ctx, org.ID, owner.ID, mTarget.ID.String(), authz.RoleOwner)
+		s.NoError(err)
+
+		memberships, count, err := s.Membership.ByOrg(ctx, org.ID, &biz.ListByOrgOpts{}, nil)
+		s.NoError(err)
+		s.Equal(2, count) // only owner and admin remain
+		s.Len(memberships, 2)
+	})
+}
+
 func (s *membershipIntegrationTestSuite) TestCreateMembership() {
 	assert := assert.New(s.T())
 	ctx := context.Background()