diff --git a/ui/src/api/wfe.js b/ui/src/api/wfe.js
index b7963c03b9..c4874e2bc5 100644
--- a/ui/src/api/wfe.js
+++ b/ui/src/api/wfe.js
@@ -78,7 +78,7 @@ router.get('/search-by-task/:taskId', async (req, res, next) => {
 
     let query = req.query.q || '';
     const url =
-      baseURL2 + 'search-by-tasks?size=100&sort=startTime:DESC&freeText=' + freeText.join(' AND ') + '&start=' + start;
+      baseURL2 + 'search-by-tasks?size=100&sort=startTime:DESC&freeText=' + encodeURIComponent(freeText.join(' AND ')) + '&start=' + start;
     const result = await http.get(url, req.token);
 
     const hits = result.results;