diff --git a/apps/dav/lib/CalDAV/CalDavBackend.php b/apps/dav/lib/CalDAV/CalDavBackend.php
index 86ed21795f4c1..b3b9ebf4238bd 100644
--- a/apps/dav/lib/CalDAV/CalDavBackend.php
+++ b/apps/dav/lib/CalDAV/CalDavBackend.php
@@ -3914,11 +3914,13 @@ public function pruneOutdatedSyncTokens(int $keep, int $retention): int {
 			return 0;
 		}
 
+		$cutoff = max(0, time() - $retention);
+
 		$query = $this->db->getQueryBuilder();
 		$query->delete('calendarchanges')
 			->where(
 				$query->expr()->lte('id', $query->createNamedParameter($maxId - $keep, IQueryBuilder::PARAM_INT), IQueryBuilder::PARAM_INT),
-				$query->expr()->lte('created_at', $query->createNamedParameter($retention)),
+				$query->expr()->lte('created_at', $query->createNamedParameter($cutoff, IQueryBuilder::PARAM_INT), IQueryBuilder::PARAM_INT),
 			);
 		return $query->executeStatement();
 	}
diff --git a/apps/dav/lib/CardDAV/CardDavBackend.php b/apps/dav/lib/CardDAV/CardDavBackend.php
index 3d26ef9507efd..8c4da892e041f 100644
--- a/apps/dav/lib/CardDAV/CardDavBackend.php
+++ b/apps/dav/lib/CardDAV/CardDavBackend.php
@@ -1527,11 +1527,13 @@ public function pruneOutdatedSyncTokens(int $keep, int $retention): int {
 			return 0;
 		}
 
+		$cutoff = max(0, time() - $retention);
+
 		$query = $this->db->getQueryBuilder();
 		$query->delete('addressbookchanges')
 			->where(
 				$query->expr()->lte('id', $query->createNamedParameter($maxId - $keep, IQueryBuilder::PARAM_INT), IQueryBuilder::PARAM_INT),
-				$query->expr()->lte('created_at', $query->createNamedParameter($retention)),
+				$query->expr()->lte('created_at', $query->createNamedParameter($cutoff, IQueryBuilder::PARAM_INT), IQueryBuilder::PARAM_INT),
 			);
 		return $query->executeStatement();
 	}
diff --git a/apps/dav/tests/unit/CalDAV/CalDavBackendTest.php b/apps/dav/tests/unit/CalDAV/CalDavBackendTest.php
index 75bd0f118906f..a45ee73cd2e06 100644
--- a/apps/dav/tests/unit/CalDAV/CalDavBackendTest.php
+++ b/apps/dav/tests/unit/CalDAV/CalDavBackendTest.php
@@ -1531,11 +1531,12 @@ public function testPruneOutdatedSyncTokens(): void {
 EOD;
 		$this->backend->updateCalendarObject($calendarId, $uri, $calData);
 
-		// Keep everything
-		$deleted = $this->backend->pruneOutdatedSyncTokens(0, 0);
+		// Keep everything by using a retention duration larger than the row age
+		$deleted = $this->backend->pruneOutdatedSyncTokens(0, time());
 		self::assertSame(0, $deleted);
 
-		$deleted = $this->backend->pruneOutdatedSyncTokens(0, time());
+		// A retention duration of 0 means everything older than "now" is eligible
+		$deleted = $this->backend->pruneOutdatedSyncTokens(0, 0);
 		// At least one from the object creation and one from the object update
 		$this->assertGreaterThanOrEqual(2, $deleted);
 		$changes = $this->backend->getChangesForCalendar($calendarId, $syncToken, 1);
@@ -1601,7 +1602,7 @@ public function testPruneOutdatedSyncTokens(): void {
 		$this->assertEmpty($changes['deleted']);
 
 		// Delete all but last change
-		$deleted = $this->backend->pruneOutdatedSyncTokens(1, time());
+		$deleted = $this->backend->pruneOutdatedSyncTokens(1, 0);
 		$this->assertEquals(1, $deleted); // We had two changes before, now one
 
 		// Only update should remain
@@ -1611,7 +1612,7 @@ public function testPruneOutdatedSyncTokens(): void {
 		$this->assertEmpty($changes['deleted']);
 
 		// Check that no crash occurs when prune is called without current changes
-		$deleted = $this->backend->pruneOutdatedSyncTokens(1, time());
+		$deleted = $this->backend->pruneOutdatedSyncTokens(1, 0);
 		self::assertSame(0, $deleted);
 	}
 
diff --git a/apps/dav/tests/unit/CardDAV/CardDavBackendTest.php b/apps/dav/tests/unit/CardDAV/CardDavBackendTest.php
index df7b99a84bcc1..03d049b34da83 100644
--- a/apps/dav/tests/unit/CardDAV/CardDavBackendTest.php
+++ b/apps/dav/tests/unit/CardDAV/CardDavBackendTest.php
@@ -922,11 +922,12 @@ public function testPruneOutdatedSyncTokens(): void {
 		$this->backend->createCard($addressBookId, $uri, $this->vcardTest0);
 		$this->backend->updateCard($addressBookId, $uri, $this->vcardTest1);
 
-		// Do not delete anything if week data as old as ts=0
-		$deleted = $this->backend->pruneOutdatedSyncTokens(0, 0);
+		// Keep everything by using a retention duration larger than the row age
+		$deleted = $this->backend->pruneOutdatedSyncTokens(0, time());
 		self::assertSame(0, $deleted);
 
-		$deleted = $this->backend->pruneOutdatedSyncTokens(0, time());
+		// A retention duration of 0 means everything older than "now" is eligible
+		$deleted = $this->backend->pruneOutdatedSyncTokens(0, 0);
 		// At least one from the object creation and one from the object update
 		$this->assertGreaterThanOrEqual(2, $deleted);
 		$changes = $this->backend->getChangesForAddressBook($addressBookId, $syncToken, 1);
@@ -958,7 +959,7 @@ public function testPruneOutdatedSyncTokens(): void {
 		$this->assertEmpty($changes['deleted']);
 
 		// Delete all but last change
-		$deleted = $this->backend->pruneOutdatedSyncTokens(1, time());
+		$deleted = $this->backend->pruneOutdatedSyncTokens(1, 0);
 		$this->assertEquals(1, $deleted); // We had two changes before, now one
 
 		// Only update should remain
@@ -968,6 +969,6 @@ public function testPruneOutdatedSyncTokens(): void {
 		$this->assertEmpty($changes['deleted']);
 
 		// Check that no crash occurs when prune is called without current changes
-		$deleted = $this->backend->pruneOutdatedSyncTokens(1, time());
+		$deleted = $this->backend->pruneOutdatedSyncTokens(1, 0);
 	}
 }