CNIT 127: Exploit Development

Spring 2021 Sam Bowne

33192 Mon 6:10 - 9 PM

Schedule · Lecture Notes · Projects · Grading

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To attend class:

The old zoom link was
Password: student1

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Catalog Description

Learn how to find vulnerabilities and exploit them to gain control of target systems, including Linux, Windows, Mac, and Cisco. This class covers how to write tools, not just how to use them; essential skills for advanced penetration testers and software security professionals.

Advisory: CS 110A or equivalent familiarity with programming

Upon successful completion of this course, the student will be able to:

  • Define and explain essential Windows features and their weaknesses
  • Research, discover and exploit vulnerabilities in Mac OS X as part of ethical, authorized penetration tests
  • Research, discover and exploit vulnerabilities in Cisco lOS as part of ethical, authorized penetration tests
  • Evaluate and implement protection mechanisms


"The Shellcoder's Handbook: Discovering and Exploiting Security Holes ", by Chris Anley, John Heasman, Felix Lindner, Gerardo Richarte; ASIN: B004P5O38Q Buy from Amazon


The quizzes are multiple-choice, online, and open-book. However, you may not ask other people to help you during the quizzes. You will need to study the textbook chapter before the lecture covering it, and take the quiz before that class. Each quiz is due 30 min. before class. Each quiz has 5 questions, you have ten minutes to take it, and you can make two attempts. If you take the quiz twice, the higher score counts.

CCSF students should take quizzes in the CCSF online Canvas system:

Non-CCSF students Enroll Here (reset password, if needed)

Discussion Board

Each CCSF student must contribute to the Discussion Board in Canvas. There are dates listed in the schedule with Discussion assignment due.

For the topics and requirements, see the Discussion board in Canvas.

Non-CCSF students don't have a Discussion Board in Canvas, but are encouraged to join Twitter and engage in the public discussions there.


For class-related questions, please send messages inside Canvas or email



Mon 1-25  Ch 1: Before you Begin

Mon 2-1 No Quiz Guest: Bharani Rajakumar
Virtual Reality: Use It To Change The World
More info & Zoom link:

Mon 2-8 Ch 1 Quiz*
Ch 2 Quiz*
Proj ED 30 due *
Ch 2: Stack overflows on Linux

Mon 2-15 Holiday: No Class

Mon 2-22 Ch 3 Quiz
Proj ED 101 & 102 due
Ch 3: Shellcode

Mon 3-1 No Quiz Guest: Nathan Iverson
Tech Sales
More info & Zoom link:

Mon 3-8 Ch 4 Quiz
Proj ED 103 & 104 due   
Ch 4: Introduction to format string bugs

Mon 3-15Ch 5 Quiz
Proj ED 201 & 202 due
Ch 5: Introduction to heap overflows

Mon 3-22 No Quiz
Proj ED 203 & 204 due
Ch 6: The Wild World of Windows & Proj ED 308 Demonstration

Mon 3-29 Holiday: No Class

Mon 4-5 No Quiz TechTalk and Q&A Session with Kristin Hoyne-Gomes
More info & Zoom link:

Mon 4-12 Ch 6 Quiz
Proj ED 205 & 206 due
Lecture 7: Intro to 64-Bit Assembler (Not in book)
ED 230: Hardening ELF Binaries

Mon 4-19 Ch 8a Quiz
Proj ED 207 & 220 due
Ch 8: Windows overflows (Part 1)
ED 319: SEH-Based Stack Overflow Exploit

Mon 4-26 Ch 8b Quiz
Proj H 2 & ED 308 due
Ch 8: Windows overflows (Part 2)
Demo: ED 330 & 331, R 10 & 20

Mon 5-3 No Quiz Mary Gardner, Former CISO, F5
More info & Zoom link:

Mon 5-10 No Quiz Bob Fabien Zinga, Director, Information Security, Directly
More info & Zoom link:

Mon 5-17 Ch 14 Quiz
Proj ED 301 & 302 due
Last Class
Special Event for CCSF Cybersecurity Students
Zoom link TBA

Mon 5-19 -  
Mon 5-26
Final Exam available online throughout the week.
You can only take it once.

All Quizzes due 30 min. before class
* Not counted as late until 2-8


Grading Policy

Introduction to Exploitation: Linux on x86

Ch 1: Before you begin · KEY · PDF
Ch 2: Stack overflows on Linux · KEY · PDF (updated 2-8-21)
Ch 3: Shellcode · KEY · PDF (updated 2-22-21)
Ch 4: Introduction to format string bugs · KEY · PDF (rev. 2-28-21)
Ch 5: Introduction to heap overflows · KEY · PDF (rev. 3-14-21)


Ch 6: The Wild World of Windows · KEY
Lecture 7: Intro to 64-Bit Assembler (Not in book) · KEY · PDF (rev. 4-12-21)

We'll skip Ch 7: Windows shellcode

Ch 8: Windows overflows (Part 1) · KEY · PDF (rev. 4-18-21)
Ch 8: Windows overflows (Part 2) · KEY
L 9: Web Templates and .NET (not in book) · KEY · PDF

We'll skip chapters 9 through 13

Ch 14: Protection Mechanisms · KEY

Vulnerability Discovery

We'll skip chapter 15

Ch 16: Fault Injection and 17: The Art of Fuzzing · KEY
Ch 18: Source Code Auditing · KEY

Exploiting Windows: Introduction
Buffer Overflow Defenses

Links for Chapter Lectures

Ch 1a: Anatomy of a Program in Memory - Excellent explanation from 2009
Ch 1b: assembly - difference between 'or eax,eax' and 'test eax,eax'

Ch 2a: Smashing the Stack for Fun and Profit by Aleph One
Ch 2b: Assembly Programming Tutorial
Ch 2c: GDB Command Reference - set disassembly-flavor command
Ch 2d: GDB Tutorial

Ch 3b: What's the difference of the Userland vs the Kernel?
Ch 3c: Protection ring - Wikipedia
Ch 3d: The GNU C Library: glibc
Ch 3e: linux - What is the difference between exit() and exit_group()
Ch 3f: Two excellent syscall examples with explanations
Ch 3g: c - Linux system call table or cheetsheet in assembly language - Stack Overflow
Ch 3h: NASM Tutorial
Ch 3i: Shellcode in C - What does this mean? - Stack Overflow
Ch 3k: C code to test shellcode, simpler than that in the textbook
Ch 3l: execve(2): execute program - Linux man page
Ch 3m: Linux Syscall Reference
Ch 3n: Ways to do syscall: INT 0x80 and call *%gs:0x10 explained

Ch 4a: Format String Exploitation-Tutorial By Saif El-Sherel (updated 1-25-18, ty B Meixell)
Ch 4b: Exploiting Format String Vulnerabilities (from 2001)
Ch 4c: Advanced Format String Attacks (Paul Haas, Slides from DEF CON 18)
Ch 4d: Advanced Format String Attacks with demo videos
Ch 4e: Defcon 18 - Advanced format string attacks Paul Haas - YouTube
Ch 4f: Introduction to format string exploits -- with helpful gdb tips
Ch 4g: Ace Stream Media Format String Vulnerability (from 2014)
Ch 4h: Cisco Email Security Appliance Format String Vulnerability (9-9-2015)
Ch 4i: Graphviz Remote Format String Vulnerability, affects Ubuntu (from 2014)
Ch 4j: Polycom - H.323 Format String Vulnerability (from 2013)
Ch 4k: Python RRDtool Module Function Format String Vulnerability (from 2013)
Ch 4l: Broadcom UPnP Stack Format String Vulnerability (from 2013)
Ch 4m: pidgin-otr log_message_cb() Function Format String Vulnerability (from 2012)
Ch 4n: atexit(3) - Linux man page
Ch 4o: GOT and PLT for pwning
Ch 4p: PLT and GOT - the key to code sharing and dynamic libraries

Ch 5a: A Memory Allocator by Doug Lea
Ch 5b: Understanding the Heap & Exploiting Heap Overflows
Ch 5c: Several Interesting Heap Overflow Example Programs
Ch 5d: Four Excellent Heap Overflow Exercises (updated 1-25-18, ty B Meixell)
Ch 5e: Wonderful Exploit Exercises including VMs and heap overflows
Ch 5f: Dangling Pointer paper from Black Hat 2007
Ch 5g: Working example of a "Dangling Pointers" exploit?
Ch 5h: Dangling Pointers: Vulnerability and Exploitation Basics
Ch 5i: Much ado about NULL: Exploiting a kernel NULL dereference
Ch 5j: HEAP BASED EXPLOITATION. Scott Hand CSG 2/22/12 - PDF (link working 2-28-18)

Ch 6a: theForger's Win32 API Tutorial
Ch 6b: Process Explorer
Ch 6c: Portable Executable - Wikipedia
Ch 6d: PEview (PECOFF file viewer)
Ch 6e: Rebasing Win32 DLLs
Ch 6f: Why is 0x00400000 the default base address for an executable?
Ch 6g: VA (Virtual Adress) & RVA (Relative Virtual Address) - Stack Overflow
Ch 6h: Exploiting the LNK Vulnerability with Metasploit
Ch 6i: Is there any difference between a GUID and a UUID? - Stack Overflow
Ch 6j: Service Control Manager - Wikipedia
Ch 6k: Microsoft RPC Remote Procedure Call and End Point Mapper with Network Traces
Ch 6l: Setting Up Kernel-Mode Debugging over a Network Cable Manually (Windows Debuggers)
Ch 6k: IMMUNITY Debugger
Ch 6l: Operating Systems Development - Portable Executable (PE)
Ch 6m: RPC Endpoint Mapper in a network trace

L7a: AMD64 Architecture Processor (pdf, downloads immediately) (updated 1-25-18, ty B Meixell)
L7b: x64 Architecture - Windows 10 hardware dev
L7c: Introduction to x64 Assembly | Intel Developer Zone
L7d: Behind Windows x64's 44-bit Virtual Memory Addressing Limit
L7e: Windows 8.1 removes the 44-bit limitation (2015)
L7f: X86-64 (AMD64) Tutorial
L7g: AMD CPUID Specification
L7h: Searchable Linux Syscall Table for x86 and x86_64
L7i: Intel® 64 and IA-32 Architectures Software Developer’s Manual
L7j: 64-bit Linux stack smashing tutorial: Part 1
L7k: x86-64 - Wikipedia--AMD 64-bit processors only use 48-bit address space
L7l: Linux/x86_64 execve"/bin/sh"; shellcode 30 bytes
L7m: Writing shellcode for Linux and *BSD - Spawning a shell
L7n: Execve Shellcode 64 bit
L7o: Writing 64-Bit Shellcode - Part 1
L7p: 64 Bits Linux Stack Based Buffer Overflow (updated 1-25-18, ty B Meixell)
L7q: memory management - What and where are the stack and heap? - Stack Overflow

Ch 8a: Win32 Thread Information Block - Wikipedia
Ch 8b: TEB structure (Windows)
Ch 8c: Process Environment Block - Wikipedia
Ch 8d: PEB structure (Windows)
Ch 8e: assembly - What is the "FS" "GS" register intended for? - Stack Overflow
Ch 8f: Preventing the Exploitation of Structured Exception Handler (SEH) Overwrites with SEHOP (2009)
Ch 8h: SEH Based Overflow Exploit Tutorial - InfoSec Resources
Ch 8i: Windows ISV Software Security Defenses (2010)
Ch 8j: Software Defense: mitigating stack corruption vulnerabilities (2014)
Ch 8k: SEHOP per-process opt-in support in Windows 7
Ch 8l: Vista SP1 and Server 2008: Controlling SEHOP security protection
Ch 8m: Reducing the Effective Entropy of GS Cookies (2007)
Ch 8n: HeapCreate function (Windows)
Ch 8o: Heap Overflow: Vulnerability and Heap Internals Explained - InfoSec Resources
Ch 8p: Intercepting Calls to COM Interfaces - CodeProject
Ch 8q: Exploiting Lingering Vulnerabilities in Default COM Objects (pdf, 2011)
Ch 8r: OLE/COM Object Viewer Download
Ch 8s: Active X Exploitation - InfoSec Resources
Ch 8u: Dranzer | Vulnerability Analysis | The CERT Division
Ch 8v: dranzer download |
Ch 8w: dzzie/COMRaider on GitHub
Ch 8x: ActiveX vulnerabilities exploitation (from 2010)
Ch 8y: Win32 Thread Information Block - Wikipedia
Ch 8qq: No Loitering: Exploiting Lingering Vulnerabilities in Default COM Objects (paper) | Internet Society
Ch 14a: What is
Ch 14b: Heap overflow using Malloc Maleficarum
Ch 14c: Windows 8 Heap Internals
Ch 14d: RdRand - Wikipedia
Ch 14e: "We cannot trust" Intel and Via's chip-based crypto, FreeBSD developers say
Ch 14f: Windows 10 security overview
Ch 14g: Windows heap cookie is only 8 bits long

Ch 17a: Awesome-Fuzzing: A curated list of fuzzing resources ( Books, courses - free and paid, videos, tools, tutorials and vulnerable applications to practice on )

Ch 18a: Cscope Home Page
Ch 18b: Using Cscope on large projects (example: the Linux kernel)
Ch 18c: Exuberant Ctags
Ch 18d: Splint Home Page
Ch 18e: Splint the static C code checker
CH 18g: More Tricks For Defeating SSL In Practice
Ch 18h: CVE-2003-0161 -- Sendmail prescan() function vulnerability
Ch 18i: Port 25 (SMTP) - Remote Sendmail Header Processing Vulnerability
Ch 18j: PHP Hash Comparison Weakness A Threat To Websites, Researcher Says
Ch 18k: Dangling pointer - Wikipedia
Ch 18l: How to Create a Secure Login Script in PHP and MySQL - wikiHow

Fuzz 1: Failure Observation Engine (FOE) tutorial - YouTube
Fuzz 2: Fuzz Testing for Dummies (2011)
Fuzz 3: Analyze Crashes to Find Security Vulnerabilities in Your Apps
Fuzz 4: VBinDiff - Visual Binary Diff
Fuzz 5: vbindiff(1) - Linux man page
Fuzz 6: An Introduction to Fuzzing: Using fuzzers (SPIKE) to find vulnerabilities - InfoSec Resources
Fuzz 7: Fuzzing with Peach Part 1
Fuzz 8: GlobalSCAPE CuteZIP Stack Buffer Overflow | Rapid7
Fuzz 9: Android Intent Fuzzer
Fuzz 10: Basic Fuzzing Framework (BFF) | Vulnerability Analysis | The CERT Division
Fuzz 11: HOWTO : CERT Basic Fuzzing Framework (BFF) on Ubuntu Desktop 12.04 LTS
Fuzz 12: Fuzzer Automation with SPIKE - InfoSec Resources
Fuzz 13: Fuzzing with Spike to Find Overflows
Fuzz 14: [Python] IRC Fuzzer -
Fuzz 15: american fuzzy lop
Fuzz 16: Bug Hunting Using Fuzzing and Static Analysis
Fuzz 17: Fuzzing Tools in Kali Linux

Ch 16a: Socket.NoDelay Property
Ch 16b: Flawfinder Home Page

Hopper 1: Use The Debugger with Hopper Disassembler/Decompiler - YouTube
Hopper 2: Tutorial
Hopper 3: Hopper Download
Hopper 4: Linux Installation
Hopper 5: Intro to Hopper - YouTube
Hopper 6: Crackmes | Reverse Engineering Mac OS X
Hopper 7: Linux x86 Program Start Up -- EXCELLENT EXPLANATION

Miscellaneous Links

SmashTheStack Wargaming Network
Great exploit tutorials from 2012 in the WayBack Machine
Exploit Exercises -- useful exploits and shells
Bypassing AV Scanners -- OLLYDBG PROJECT IN HERE
Valgrind Tutorial
Bypassing EMET's EAF with custom shellcode using kernel pointer (from 2011)
Disarming Enhanced Mitigation Experience Toolkit (EMET) v 5.0
Rootkits by Csaba Barta (from 2009) (updated 1-25-18, ty B Meixell)
PSA: don't run 'strings' on untrusted files -- WORTH EXPLOITING
From 0-day to exploit -- Buffer overflow in Belkin N750 (CVE-2014-1635)
Disarming and Bypassing EMET 5.1
BinScope Binary Analyzer -- vulnerability detector
Popular security suites open to attack -- DEP and ASLR Not Enabled
GDB: Debugging stripped binaries
PBKDF2 - Wikipedia
Installing VMware Tools on Kali Linux
Kali Linux Downloads
IMMUNITY : Download
How to setup Dark Comet RAT (with download and pictures) : hacking
Cython: C-Extensions for Python -- MAKES SMALL EXEs
HT Editor -- powerful binary ELF editor
ntpdc local buffer overflow - Exploit Development example, interesting GDB commands
Seven Resume Strategies for the Long-Term Unemployed
KdExploitMe - Hackable Windows Kernel Driver -- USE FOR PROJECTS
64-bit Linux Return-Oriented Programming
Exploit Exercises -- GOOD FOR PROJECTS
WIRESHARK 1.12.4 and below Access Violation and Memory Corruption PoC
Fuzzing with AFL-Fuzz, a Practical Example ( AFL vs binutils ) -- USEFUL FOR PROJECT
Radare portable reversing framework
Hopper: The OS X and Linux Disassembler -- GOOD FOR PROJECTS
Gdbinit: user-friendly gdb configuration file -- GOOD FOR PROJECTS
Format String Bug Exploration -USEFUL FOR PROJECT
90s-style security flaw puts "millions" of routers at risk -- LOOKS GOOD FOR A PROJECT
Exploit Development Class for Win 7 64-bit -- USEFUL FOR PROJECTS
EDB (Evan's Debugger) -- Like OllyDbg on Linux ty @offsectraining
Sophos AV Bypass - YouTube
New buffer overflow protection in gcc 4.9 -fstack-protector-strong
Old Versions of Kali Linux
Animated Metasploit Linux Payload in gdb - YouTube
Stack Smashing On A Modern Linux System
Buffer Overflow Vulnerability Lab
VMware Tools installation fails when Easy Install is in progress -- GOOD SOLUTION
Installing VMware Tools in an Ubuntu virtual machine
How to turn OFF (or at least override) syntax highlighting in nano via ~/.nanorc?
Exploit writing tutorial part 11 : Heap Spraying Demystified | Corelan Team
MemGC and Control Flow Guard (May, 2015)
How exploit writers find bugs in Java Machine? - Reverse Engineering Stack Exchange
Mac OS Xploitation (2009)
Modern Binary Exploitation class from RPI
A binary analysis, count me if you can -- VERY USEFUL
picoCTF 2014 Baleful - Solving with Pin -- INTERESTING TECHNIQUE
How to detect a NX stack and other protections against buffer overflows -- VERY USEFUL
ROP for Linux ELF files: finding JMP ESP
Performing a ret2libc Attack (updated 1-25-18, ty B Meixell)
How to disable ASLR in linux permanently.
Python multiprocessing.Pool: -- EXCELLENT EXAMPLE
Exploiting memory corruption bugs in PHP Part 3: Popping Remote Shells
Execute Bash Commands Without Spaces with Brace Expansion
x64dbg: An open-source x64/x32 debugger for windows -- ALTERNATIVE TO IDA PRO
gdb bug on 64-bit ubuntu with fix: No module name libstdcxx - Stack Overflow
gdb - debugging with pipe using mkfifio
Fuzzing on MacOS X -- MANY USEFUL TIPS
Carnegie Mellon - Tools - VulWiki
The Ultimate Disassembly Framework -- Capstone
binjitsu/binjitsu: CTF framework and exploit development library
How To Install VMware Workstation 11 On Ubuntu 14.10
Exploitation of mem-corruptions vulns in remote C/C++ programs without source or binary
Artistic Rendering of Exploit Development Process
Blind Return Oriented Programming (BROP)
Linux Assembly Tutorial - Step-by-Step Guide
A fundamental introduction to x86 assembly programming
RIP ROP: Intel's cunning plot to kill stack-hopping exploits at CPU level with "shadow stack" (June, 2016)
Introductory Intel x86: Architecture, Assembly, Applications - YouTube
Assembly Primer for Hackers (Part 1) System Organization Tutorial.mp4 - YouTube
ARM Exploitation: Return Oriented Programming on ARM (on Linux)
How to read arbitrary RAM with format string vulnerability
The best resources for learning exploit development -- MANY GOOD PROJECT IDEAS
Use The Debugger with Hopper Disassembler/Decompiler - YouTube
Over the Wire Narnia Level 2 -) 3 -- GOOD EXTRA CREDIT PROJECT
Demystifying the Execve Shellcode (Stack Method)
Program exiting after executing int 0x80 instruction when running shellcode
Debugging - Modifying Code At Runtime
How to specify base addresses for sections with gcc -- ESSENTIAL FOR KALI 2017 PROJECTS
Windows Kernel Exploitation Tutorial
[Kernel Exploitation] 2: Payloads
Infosec_Reference/Exploit Development
Requests: HTTP for Humans -- Requests 2.18.4 documentation
PEDA - Python Exploit Development Assistance for GDB
Getting cozy with exploit development
Bypassing NX/DEP -- PoC || GTFO
Simple ASLR/NX bypass on a Linux 32 bit binary
Linux Kernel Debugging with VMWare Player Free
Force GCC to push arguments on the stack before calling function (using PUSH instruction)
Analyzing Metasploit linux/x86/exec payload
Vulnserver -- GMON command SEH based overflow exploit
OakSim: ARM Assembly Simulator
ARM Assembly and Exploitation -- USEFUL FOR PROJECTS
VM of Ubuntu with ARM in QEMU
x64dbg -- Recommended by @malwareunicorn

New Unsorted Links

Radare2 Projects: "Practical case : Buffer Overflow 0x01 : 2)Methods and macros: the call stack : 3) Practical case: Patch Me 0x01 : 4)Conditions and loops : cc @LibraAnalysis"
L7r: x86-64 - Wikipedia
Immunity error: pycommands: error importing module -- caused by using 64-bit Python
The Cost of Buffer Security Checks in Visual C
Ch 14h: GS (Buffer Security Check) -- Official Microsoft Documentation
Enable or disable specific mitigations used by Exploit protection | Microsoft Docs
Control Flow Guard | Microsoft Docs
vulnserver/vulnserver.c at master � stephenbradshaw/vulnserver � GitHub
Dangling Pointers Avoid them Strictly!
Wxploiting Format Strings in Windows
6 Best Wireshark Alternatives for Android
DLL Hijacking with Ghidra--USE FOR PROJECT
wntools --CTF framework and exploit development library
Return Oriented Programming on ARM (32-bit)--USE FOR PROJECTS
Reverse Engineering with Ghidra -- USE FOR PROJECTS
Online Courses -- Ghidra
Heap Overflow Exploitation on Windows 10 Explained
Honggfuzz finding a double-free in VLC -- USE FOR PROJECT
How to Compile 32-bit Apps on 64-bit Ubuntu?
Debug 32 bit application with gdb in 64 bit environment
Modern Windows Exploit Development.pdf
Dump TEB/PEB in immunitydbg - Reverse Engineering Stack Exchange
Ch 7r: Maximum addressable memory under the current operating systems
L7r: Maximum addressable memory under the current operating systems
Demystifying Dot NET Reverse Engineering, Part 1: Big Introduction
Demystifying dot NET reverse engineering - PART 2: Introducing Byte Patching
Demystifying dot NET reverse engineering - PART 3: Advanced Byte Patching
Bypassing SEHOP
DEP Bypass using ROP Chains | Garima Sinha - securityresearch - Medium
Linux Kernel ROP - Ropping your way to # (Part 1) | Trustwave | SpiderLabs | Trustwave
Libxml2 Tutorial | AFLplusplus -- FUZZER PROJECT
2020-05-13: Solving Uninitialized Stack Memory on Windows -- INTERESTING CHART OF ROOT CAUSES
Porting VulnServer TRUN /.:/ exploit to Metasploit -- Duncan Winfrey
Bypassing SEHOP (but only 1/512 of the time)
Ch 3o: assembly - How to use sysenter under Linux?
GitHub - johnjhacking/Buffer-Overflow-Guide: This Bufferflow Guide includes instructions and the scripts necessary for Buffer Overflow Exploitation. This guide is a supplement for TheCyberMentor's walkthrough. Please watch his walkthrough if you're confused. Feel free to implement Pull Requests or raise Issues.
Labs | CyberDefenders ® | Blue Team CTF Challenges
2021-12-02: ydkhatri/mac_apt: macOS ( and ios) Artifact Parsing Tool
Learning Linux kernel exploitation - Part 1 - Laying the groundwork
Beginner Reverse Engineering Tutorials
Resources for learning exploit development
OSED - Navigating The Shadows
OSCP Guide

Last Updated: 5-19-21 7:42 pm