diff --git a/lib/libfido2/Makefile b/lib/libfido2/Makefile
index a9e1c526d45d..86ac1153f384 100644
--- a/lib/libfido2/Makefile
+++ b/lib/libfido2/Makefile
@@ -64,6 +64,7 @@ CFLAGS+= -DHAVE_SYS_RANDOM_H
 CFLAGS+= -DHAVE_TIMESPECSUB
 CFLAGS+= -DHAVE_TIMINGSAFE_BCMP
 CFLAGS+= -DHAVE_UNISTD_H
+CFLAGS+= -DOPENSSL_API_COMPAT=0x10100000L
 CFLAGS+= -DTLS=__thread
 CFLAGS+= -D_FIDO_MAJOR=1
 CFLAGS+= -D_FIDO_MINOR=10