diff --git a/pkg/internal/server/api/attachments_api.go b/pkg/internal/server/api/attachments_api.go
index f12a960..9e1b582 100644
--- a/pkg/internal/server/api/attachments_api.go
+++ b/pkg/internal/server/api/attachments_api.go
@@ -91,6 +91,7 @@ func updateAttachmentMeta(c *fiber.Ctx) error {
 
 	var data struct {
 		Alternative *string         `json:"alt"`
+		Thumbnail   *string         `json:"thumbnail"`
 		Metadata    *map[string]any `json:"metadata"`
 		IsIndexable *bool           `json:"is_indexable"`
 	}
@@ -107,6 +108,9 @@ func updateAttachmentMeta(c *fiber.Ctx) error {
 	if data.Alternative != nil {
 		attachment.Alternative = *data.Alternative
 	}
+	if data.Thumbnail != nil {
+		attachment.Thumbnail = *data.Thumbnail
+	}
 	if data.Metadata != nil {
 		attachment.Usermeta = *data.Metadata
 	}