diff --git a/upper-constraints.txt b/upper-constraints.txt
index 6fe43509b9..6aa1ffd22b 100644
--- a/upper-constraints.txt
+++ b/upper-constraints.txt
@@ -299,7 +299,7 @@ oslo.serialization===4.0.1
 warlock===1.3.3
 exabgp===4.2.11
 sphinxcontrib-httpdomain===1.7.0
-metalsmith===1.3.0
+metalsmith===1.4.0
 s3transfer===0.3.3
 text-unidecode===1.3
 sphinxcontrib-svg2pdfconverter===1.1.0