diff --git a/docs/hazmat/primitives/cryptographic-hashes.rst b/docs/hazmat/primitives/cryptographic-hashes.rst
index b0e9c16..fd5f35d 100644
--- a/docs/hazmat/primitives/cryptographic-hashes.rst
+++ b/docs/hazmat/primitives/cryptographic-hashes.rst
@@ -120,7 +120,9 @@
 BLAKE2
 ~~~~~~
 
-`BLAKE2`_ is a cryptographic hash function specified in :rfc:`7693`.
+`BLAKE2`_ is a cryptographic hash function specified in :rfc:`7693`. BLAKE2's
+design makes it immune to `length-extension attacks`_, an advantage over the
+SHA-family of hashes.
 
 .. note::
 
@@ -224,3 +226,4 @@
 
 .. _`Lifetimes of cryptographic hash functions`: http://valerieaurora.org/hash.html
 .. _`BLAKE2`: https://blake2.net
+.. _`length-extension attacks`: https://en.wikipedia.org/wiki/Length_extension_attack
diff --git a/docs/spelling_wordlist.txt b/docs/spelling_wordlist.txt
index 04ec0e6..f60943a 100644
--- a/docs/spelling_wordlist.txt
+++ b/docs/spelling_wordlist.txt
@@ -69,6 +69,7 @@
 scrypt
 serializer
 Serializers
+SHA
 Solaris
 Tanja
 testability