diff --git a/book/source/03-cryptography.md b/book/source/03-cryptography.md
index 58ab78e..d249a9f 100644
--- a/book/source/03-cryptography.md
+++ b/book/source/03-cryptography.md
@@ -54,7 +54,7 @@ Public-key cryptography doesn't require participants to pre-arrange a shared sec
 
 In many places, we'll deal with asymmetric cryptographic key pairs:
 
-```{figure} diag/cryptographic_keys.png
+```{figure} diag/cryptographic_keypair.svg
 ---
 ---
 An asymmetric cryptographic key pair