diff --git a/docs/必学工具/tools.md b/docs/必学工具/tools.md
index 206d2404..ca554317 100644
--- a/docs/必学工具/tools.md
+++ b/docs/必学工具/tools.md
@@ -3,6 +3,7 @@
 - [Libgen](http://libgen.is/)：PDF电子书下载网站。
 - [z-epub](https://z-epub.com/)：ePub电子书下载网站。
 - [bitdownloader](https://bitdownloader.io/)：油管视频下载器。
+- [zlibrary](https://1lib.limited/)：电子书下载网站(可能需要翻墙)。
 
 ## 设计工具
 - [excalidraw](https://excalidraw.com/%E4%B9%88)：一款手绘风格的绘图工具，非常适合绘制课程报告或者PPT内的示意图。
diff --git a/docs/系统安全/MIT6.858.md b/docs/系统安全/MIT6.858.md
new file mode 100644
index 00000000..59b36edf
--- /dev/null
+++ b/docs/系统安全/MIT6.858.md
@@ -0,0 +1,24 @@
+## 课程简介
+- 所属大学：MIT
+- 先修要求:
+- 编程语言：C, Python
+- 课程难度：🌟🌟🌟🌟🌟
+- 预计学时：150小时
+
+MIT的计算机系统安全课程，实验环境是一个Web Application Zoobar. 学生学习攻防技术并应用于该Web Application. 
+
+-   Lab 1: you will explore the zoobar web application, and use buffer overflow attacks to break its security properties.
+-   Lab 2: you will improve the zoobar web application by using privilege separation, so that if one component is compromised, the adversary doesn't get control over the whole web application.
+-   Lab 3: you will build a program analysis tool based on symbolic execution to find bugs in Python code such as the zoobar web application.
+-   Lab 4: you will improve the zoobar application against browser attacks.
+
+这个课我主要是做了lab3,  lab3是通过混合符号执行来遍历程序的所有分支.理解了符号执行的思想后lab并不难做.这个lab直观展示符号执行这种技术的使用方法. 
+
+这个课的Final Project是实现一个SecFS,一个远端文件系统,面对完全不可信的服务器,提供机密性和完整性,[骨架代码](https://github.com/mit-pdos/secfs-skeleton),论文是[SUNDR](https://www.usenix.org/legacy/event/osdi04/tech/full_papers/li_j/li_j.pdf)
+## 课程资源
+- [课程网站](http://css.csail.mit.edu/6.858/2022/)
+- 课程视频：参见课程网站
+- 课程教材：无
+- 课程作业：4个lab + Final Project / Lab5
+
+## 资源汇总
diff --git a/mkdocs.yml b/mkdocs.yml
index 84e766bd..5b1db9aa 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -53,6 +53,7 @@ nav:
     - 'MIT 6.824: Distributed System': '并行与分布式系统/MIT6.824.md'
   - 计算机系统安全:
     - 'UCB CS161: Computer Security': '系统安全/CS161.md'
+    - 'MIT 6.858: Computer System Security': '系统安全/MIT6.858.md'
   - 计算机网络:
     - 'Computer Networking: A Top-Down Approach': '计算机网络/topdown.md'
     - 'Stanford CS144: Computer Network': '计算机网络/CS144.md'
@@ -82,4 +83,4 @@ nav:
     - 'Stanford CS224n: Natural Language Processing': '深度学习/CS224n.md'
     - 'Stanford CS224w: Machine Learning with Graphs': '深度学习/CS224w.md'
     - 'UCB CS285: Deep Reinforcement Learning': '深度学习/CS285.md'
-  - 后记: '后记.md'
\ No newline at end of file
+  - 后记: '后记.md'