diff --git a/curl.spec b/curl.spec
index 0faeab4..532f2ff 100644
--- a/curl.spec
+++ b/curl.spec
@@ -282,6 +282,10 @@ cd build-full/tests
 export OPENSSL_SYSTEM_CIPHERS_OVERRIDE=XXX
 export OPENSSL_CONF=
 
+# prevent valgrind from being extremely slow (#1662656)
+# https://fedoraproject.org/wiki/Changes/DebuginfodByDefault
+unset DEBUGINFOD_URLS
+
 # run the upstream test-suite
 srcdir=../../tests perl -I../../tests ../../tests/runtests.pl -a -p -v '!flaky'