diff --git a/gnu/packages/pdf.scm b/gnu/packages/pdf.scm
index dd221f7e19..4d3bc76473 100644
--- a/gnu/packages/pdf.scm
+++ b/gnu/packages/pdf.scm
@@ -82,6 +82,7 @@ (define-module (gnu packages pdf)
   #:use-module (gnu packages lua)
   #:use-module (gnu packages man)
   #:use-module (gnu packages markup)
+  #:use-module (gnu packages nss)
   #:use-module (gnu packages pcre)
   #:use-module (gnu packages perl)
   #:use-module (gnu packages photo)
@@ -256,6 +257,7 @@ (define-public poppler
                  libpng
                  libtiff
                  lcms
+                 nss                              ;for 'pdfsig'
                  openjpeg
                  poppler-data
                  zlib