diff --git a/include/mbedtls/cipher.h b/include/mbedtls/cipher.h
index d8e76b836..aa155d7bf 100644
--- a/include/mbedtls/cipher.h
+++ b/include/mbedtls/cipher.h
@@ -103,8 +103,8 @@ typedef enum {
 /**
  * \brief     Supported {cipher type, cipher mode} pairs.
  *
- * \warning   RC4 and DES are considered weak ciphers and their use
- *            constitutes a security risk. Arm recommends considering stronger
+ * \warning   RC4 and DES/3DES are considered weak ciphers and their use
+ *            constitutes a security risk. We recommend considering stronger
  *            ciphers instead.
  */
 typedef enum {
@@ -140,12 +140,12 @@ typedef enum {
     MBEDTLS_CIPHER_CAMELLIA_128_GCM,     /**< Camellia cipher with 128-bit GCM mode. */
     MBEDTLS_CIPHER_CAMELLIA_192_GCM,     /**< Camellia cipher with 192-bit GCM mode. */
     MBEDTLS_CIPHER_CAMELLIA_256_GCM,     /**< Camellia cipher with 256-bit GCM mode. */
-    MBEDTLS_CIPHER_DES_ECB,              /**< DES cipher with ECB mode. */
-    MBEDTLS_CIPHER_DES_CBC,              /**< DES cipher with CBC mode. */
-    MBEDTLS_CIPHER_DES_EDE_ECB,          /**< DES cipher with EDE ECB mode. */
-    MBEDTLS_CIPHER_DES_EDE_CBC,          /**< DES cipher with EDE CBC mode. */
-    MBEDTLS_CIPHER_DES_EDE3_ECB,         /**< DES cipher with EDE3 ECB mode. */
-    MBEDTLS_CIPHER_DES_EDE3_CBC,         /**< DES cipher with EDE3 CBC mode. */
+    MBEDTLS_CIPHER_DES_ECB,              /**< DES cipher with ECB mode. \warning DES is considered weak. */
+    MBEDTLS_CIPHER_DES_CBC,              /**< DES cipher with CBC mode. \warning DES is considered weak. */
+    MBEDTLS_CIPHER_DES_EDE_ECB,          /**< DES cipher with EDE ECB mode. \warning 3DES is considered weak. */
+    MBEDTLS_CIPHER_DES_EDE_CBC,          /**< DES cipher with EDE CBC mode. \warning 3DES is considered weak. */
+    MBEDTLS_CIPHER_DES_EDE3_ECB,         /**< DES cipher with EDE3 ECB mode. \warning 3DES is considered weak. */
+    MBEDTLS_CIPHER_DES_EDE3_CBC,         /**< DES cipher with EDE3 CBC mode. \warning 3DES is considered weak. */
     MBEDTLS_CIPHER_BLOWFISH_ECB,         /**< Blowfish cipher with ECB mode. */
     MBEDTLS_CIPHER_BLOWFISH_CBC,         /**< Blowfish cipher with CBC mode. */
     MBEDTLS_CIPHER_BLOWFISH_CFB64,       /**< Blowfish cipher with CFB64 mode. */
@@ -226,11 +226,11 @@ typedef enum {
 enum {
     /** Undefined key length. */
     MBEDTLS_KEY_LENGTH_NONE = 0,
-    /** Key length, in bits (including parity), for DES keys. */
+    /** Key length, in bits (including parity), for DES keys. \warning DES is considered weak. */
     MBEDTLS_KEY_LENGTH_DES  = 64,
-    /** Key length in bits, including parity, for DES in two-key EDE. */
+    /** Key length in bits, including parity, for DES in two-key EDE. \warning 3DES is considered weak. */
     MBEDTLS_KEY_LENGTH_DES_EDE = 128,
-    /** Key length in bits, including parity, for DES in three-key EDE. */
+    /** Key length in bits, including parity, for DES in three-key EDE. \warning 3DES is considered weak. */
     MBEDTLS_KEY_LENGTH_DES_EDE3 = 192,
 };