diff --git a/src/libstrongswan/credentials/certificates/crl.h b/src/libstrongswan/credentials/certificates/crl.h
index 224585fb2..94de44c44 100644
--- a/src/libstrongswan/credentials/certificates/crl.h
+++ b/src/libstrongswan/credentials/certificates/crl.h
@@ -28,9 +28,10 @@ typedef enum crl_reason_t crl_reason_t;
 #include <library.h>
 #include <credentials/certificates/certificate.h>
 
-/* <wincrypt.h> comes with CRL_REASON clashing with ours. Even if the values
- * are identical, we undef them here to use our enum instead of defines. */
-#ifdef WIN32
+/* <wincrypt.h> comes with CRL_REASON clashing with ours. The same is true for
+ * OpenSSL 3.0. Even if the values are identical, we undef them here to use our
+ * enum instead of defines. */
+#ifdef CRL_REASON_UNSPECIFIED
 # undef CRL_REASON_UNSPECIFIED
 # undef CRL_REASON_KEY_COMPROMISE
 # undef CRL_REASON_CA_COMPROMISE