diff --git a/lib/Dav/Faces/FaceRoot.php b/lib/Dav/Faces/FaceRoot.php
index 97b0d8625..6df6babfd 100644
--- a/lib/Dav/Faces/FaceRoot.php
+++ b/lib/Dav/Faces/FaceRoot.php
@@ -114,7 +114,7 @@ public function getChild($name): FacePhoto {
 		} catch (DoesNotExistException $e) {
 			throw new NotFound();
 		}
-		if ($detection->getClusterId() !== $this->cluster->getId()) {
+		if ($detection->getUserId() !== $this->user->getUID() || $detection->getClusterId() !== $this->cluster->getId()) {
 			throw new NotFound();
 		}
 		return new FacePhoto($this->detectionMapper, $detection, $this->rootFolder->getUserFolder($this->user->getUID()), $this->tagManager, $this->previewManager);
@@ -131,6 +131,9 @@ public function childExists($name): bool {
 
 	public function moveInto($targetName, $sourcePath, INode $sourceNode) {
 		if ($sourceNode instanceof FacePhoto) {
+			if ($sourceNode->getFaceDetection()->getUserId() !== $this->user->getUID()) {
+				throw new Forbidden('Not allowed to move face detections of other users');
+			}
 			$sourceNode->getFaceDetection()->setClusterId($this->cluster->getId());
 			$this->detectionMapper->update($sourceNode->getFaceDetection());
 			return true;
diff --git a/lib/Dav/Faces/PropFindPlugin.php b/lib/Dav/Faces/PropFindPlugin.php
index 41721e2a1..d32bbdebe 100644
--- a/lib/Dav/Faces/PropFindPlugin.php
+++ b/lib/Dav/Faces/PropFindPlugin.php
@@ -20,6 +20,7 @@
 use OCP\DB\Exception;
 use OCP\Files\DavUtil;
 use OCP\IPreview;
+use OCP\IUserSession;
 use OCP\Security\ICrypto;
 use Psr\Log\LoggerInterface;
 use Sabre\DAV\Exception\Forbidden;
@@ -49,6 +50,7 @@ public function __construct(
 		private LoggerInterface $logger,
 		private ITimeFactory $timeFactory,
 		private IAppConfig $appConfig,
+		private IUserSession $userSession,
 	) {
 	}
 
@@ -61,13 +63,26 @@ public function initialize(Server $server): void {
 	}
 
 
+	/**
+	 * @return list<FaceDetectionWithTitle>
+	 * @throws Exception
+	 */
+	private function getDetections(int $fileId): array {
+		// Detections and cluster titles are private to each user
+		$userId = $this->userSession->getUser()?->getUID();
+		if ($userId === null) {
+			return [];
+		}
+		return $this->faceDetectionMapper->findByFileIdWithTitle($fileId, $userId);
+	}
+
 	public function propFind(PropFind $propFind, INode $node): void {
 		if ($node instanceof FacePhoto) {
 			$propFind->handle(self::FACE_DETECTIONS_PROPERTYNAME, function () use ($node) {
 				return json_encode(
 					array_map(
 						fn (FaceDetectionWithTitle $face) => $face->toArray(),
-						$this->faceDetectionMapper->findByFileIdWithTitle($node->getFile()->getId())
+						$this->getDetections($node->getFile()->getId())
 					)
 				);
 			});
@@ -102,7 +117,7 @@ public function propFind(PropFind $propFind, INode $node): void {
 				return json_encode(
 					array_map(
 						fn (FaceDetectionWithTitle $face) => $face->toArray(),
-						$this->faceDetectionMapper->findByFileIdWithTitle($node->getId()),
+						$this->getDetections((int)$node->getId()),
 					)
 				);
 			});
diff --git a/lib/Dav/Faces/UnassignedFacesHome.php b/lib/Dav/Faces/UnassignedFacesHome.php
index a1d491d42..d38d8cf54 100644
--- a/lib/Dav/Faces/UnassignedFacesHome.php
+++ b/lib/Dav/Faces/UnassignedFacesHome.php
@@ -76,7 +76,7 @@ public function getChild($name): UnassignedFacePhoto {
 		} catch (DoesNotExistException $e) {
 			throw new NotFound();
 		}
-		if ($detection->getClusterId() !== -1) {
+		if ($detection->getUserId() !== $this->user->getUID() || $detection->getClusterId() !== -1) {
 			throw new NotFound();
 		}
 
diff --git a/lib/Db/FaceDetectionMapper.php b/lib/Db/FaceDetectionMapper.php
index 939205429..5f2c28e3d 100644
--- a/lib/Db/FaceDetectionMapper.php
+++ b/lib/Db/FaceDetectionMapper.php
@@ -179,14 +179,16 @@ public function assocWithCluster(FaceDetection $faceDetection, FaceCluster $face
 
 	/**
 	 * @param int $fileId
+	 * @param string $userId
 	 * @return list<\OCA\Recognize\Db\FaceDetectionWithTitle>
 	 * @throws \OCP\DB\Exception
 	 */
-	public function findByFileIdWithTitle(int $fileId) : array {
+	public function findByFileIdWithTitle(int $fileId, string $userId) : array {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select(array_merge(array_map(fn ($col) => 'd.'.$col, FaceDetection::$columns), ['c.title']))
 			->from('recognize_face_detections', 'd')
 			->where($qb->expr()->eq('file_id', $qb->createPositionalParameter($fileId, IQueryBuilder::PARAM_INT)))
+			->andWhere($qb->expr()->eq('d.user_id', $qb->createPositionalParameter($userId, IQueryBuilder::PARAM_STR)))
 			->leftJoin('d', 'recognize_face_clusters', 'c', $qb->expr()->eq('d.cluster_id', 'c.id'));
 		/** @var list<\OCA\Recognize\Db\FaceDetectionWithTitle> $entities */
 		$entities = $this->findEntities($qb);