diff --git a/_posts/Lecture Notes/Internet Security/2023-09-18-symmetric-key-cryptography-2.md b/_posts/Lecture Notes/Internet Security/2023-09-18-symmetric-key-cryptography-2.md
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--- a/_posts/Lecture Notes/Internet Security/2023-09-18-symmetric-key-cryptography-2.md	
+++ b/_posts/Lecture Notes/Internet Security/2023-09-18-symmetric-key-cryptography-2.md	
@@ -175,7 +175,7 @@ AES, DES use fixed block size for encryption. How do we encrypt longer messages?
 
 ### Electronic Codebook Mode (ECB)
 
-![is-03-cbc-encryption.png](../../../assets/img/posts/Lecture%20Notes/Internet%20Security/is-03-cbc-encryption.png)
+![is-03-ecb-encryption.png](../../../assets/img/posts/Lecture%20Notes/Internet%20Security/is-03-ecb-encryption.png)
 
 - Codebook is a mapping table.
 - For the $i$-th plaintext block, we use key $k$ to encrypt and obtain the $i$-th ciphertext block.
diff --git a/assets/img/posts/Lecture Notes/Internet Security/is-03-ecb-encryption.png b/assets/img/posts/Lecture Notes/Internet Security/is-03-ecb-encryption.png
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Binary files /dev/null and b/assets/img/posts/Lecture Notes/Internet Security/is-03-ecb-encryption.png differ