diff --git a/projects/libcacard/build.sh b/projects/libcacard/build.sh
index f4c823cf2..719502e90 100755
--- a/projects/libcacard/build.sh
+++ b/projects/libcacard/build.sh
@@ -15,6 +15,10 @@
 #
 ################################################################################
 
+# Workaround for fixing AFL++ build, discarded for others.
+# See https://github.com/google/oss-fuzz/issues/4280#issuecomment-773977943
+export AFL_LLVM_INSTRUMENT=CLASSIC,NGRAM-4
+
 # Compile NSS
 mkdir $SRC/nss-nspr
 mv $SRC/nss $SRC/nss-nspr/