diff --git a/include/mbedtls/config_adjust_legacy_crypto.h b/include/mbedtls/config_adjust_legacy_crypto.h
index c6b7f8e..696266c 100644
--- a/include/mbedtls/config_adjust_legacy_crypto.h
+++ b/include/mbedtls/config_adjust_legacy_crypto.h
@@ -22,6 +22,20 @@
 #ifndef MBEDTLS_CONFIG_ADJUST_LEGACY_CRYPTO_H
 #define MBEDTLS_CONFIG_ADJUST_LEGACY_CRYPTO_H
 
+/* Auto-enable CIPHER_C when any of the unauthenticated ciphers is builtin
+ * in PSA. */
+#if defined(MBEDTLS_PSA_CRYPTO_C) && \
+    (defined(MBEDTLS_PSA_BUILTIN_ALG_STREAM_CIPHER) || \
+    defined(MBEDTLS_PSA_BUILTIN_ALG_CTR) || \
+    defined(MBEDTLS_PSA_BUILTIN_ALG_CFB) || \
+    defined(MBEDTLS_PSA_BUILTIN_ALG_OFB) || \
+    defined(MBEDTLS_PSA_BUILTIN_ALG_ECB_NO_PADDING) || \
+    defined(MBEDTLS_PSA_BUILTIN_ALG_CBC_NO_PADDING) || \
+    defined(MBEDTLS_PSA_BUILTIN_ALG_CBC_PKCS7) || \
+    defined(MBEDTLS_PSA_BUILTIN_ALG_CCM_STAR_NO_TAG))
+#define MBEDTLS_CIPHER_C
+#endif
+
 /* Auto-enable MBEDTLS_MD_LIGHT based on MBEDTLS_MD_C.
  * This allows checking for MD_LIGHT rather than MD_LIGHT || MD_C.
  */