Bento4 v1.6.0-639 was discovered to contain a segmentation violation in the mp4fragment component.
# Summary
Hi there, I use my fuzzer for fuzzing the binary mp4fragment, the version of Bento4 is the latest (the newest master branch) and the operation system is Ubuntu 18.04.6 LTS (docker) and this binary crashes with the following.

# Details
```
root@4e3b7f9edc0d:/mp4box/mp4fragment# ./mp4fragment ../out/crashes/id\:000000\,sig\:06\,src\:000008\,op\:flip1\,pos\:31325\,4970731 /dev/null
unable to autodetect fragment duration, using default
AddressSanitizer:DEADLYSIGNAL
=================================================================
==750986==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 0x7f5fc13c0306 bp 0x7ffe16f62f30 sp 0x7ffe16f626c8 T0)
==750986==The signal is caused by a READ memory access.
==750986==Hint: address points to the zero page.
    #0 0x7f5fc13c0306  (/lib/x86_64-linux-gnu/libc.so.6+0xb1306)
    #1 0x94da2c in __interceptor_strlen.part.36 /llvm-project/compiler-rt/lib/asan/../sanitizer_common/sanitizer_common_interceptors.inc:370
    #2 0x6ec0c2 in AP4_TrakAtom::AP4_TrakAtom(AP4_SampleTable*, unsigned int, char const*, unsigned int, unsigned long long, unsigned long long, unsigned long long, unsigned int, unsigned long long, unsigned short, char const*, unsigned int, unsigned int, unsigned short, unsigned short, int const*) (/mp4box/mp4fragment/mp4fragment+0x6ec0c2)
    #3 0x432bbc in main (/mp4box/mp4fragment/mp4fragment+0x432bbc)
    #4 0x7f5fc1330c86 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21c86)
    #5 0x407cd9 in _start (/mp4box/mp4fragment/mp4fragment+0x407cd9)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV (/lib/x86_64-linux-gnu/libc.so.6+0xb1306) 
==750986==ABORTING

```
# POC
[POC-Mp4fragment-1.zip](https://github.com/axiomatic-systems/Bento4/files/9617496/POC-Mp4fragment-1.zip)


# Environment

Ubuntu 18.04.6 LTS (docker)
clang 12.0.1
clang++ 12.0.1
Bento4 master branch(5b7cc25) && Bento4 release version([1.6.0-639](https://www.bok.net/Bento4/binaries/Bento4-SDK-1-6-0-639.x86_64-unknown-linux.zip))


# Credit
Xudong Cao ([NCNIPC of China](http://www.nipc.org.cn/)), (Zhongguancun Laboratory)
Jiayuan Zhang ([NCNIPC of China](http://www.nipc.org.cn/)), (Zhongguancun Laboratory)
Han Zheng ([NCNIPC of China](http://www.nipc.org.cn/), [Hexhive](http://hexhive.epfl.ch/))

Thank you for your time!

From mp4fragment: SEGV on unknown address 0x000000000000
This is a GitHub Issue
repo:Bento4
owner:axiomatic-systems
Title : From mp4fragment: SEGV on unknown address 0x000000000000
Issue date:

--- start body ---
# Summary
Hi there, I use my fuzzer for fuzzing the binary mp4fragment, the version of Bento4 is the latest (the newest master branch) and the operation system is Ubuntu 18.04.6 LTS (docker) and this binary crashes with the following.

# Details
```
root@4e3b7f9edc0d:/mp4box/mp4fragment# ./mp4fragment ../out/crashes/id\:000000\,sig\:06\,src\:000008\,op\:flip1\,pos\:31325\,4970731 /dev/null
unable to autodetect fragment duration, using default
AddressSanitizer:DEADLYSIGNAL
=================================================================
==750986==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 0x7f5fc13c0306 bp 0x7ffe16f62f30 sp 0x7ffe16f626c8 T0)
==750986==The signal is caused by a READ memory access.
==750986==Hint: address points to the zero page.
    #0 0x7f5fc13c0306  (/lib/x86_64-linux-gnu/libc.so.6+0xb1306)
    #1 0x94da2c in __interceptor_strlen.part.36 /llvm-project/compiler-rt/lib/asan/../sanitizer_common/sanitizer_common_interceptors.inc:370
    #2 0x6ec0c2 in AP4_TrakAtom::AP4_TrakAtom(AP4_SampleTable*, unsigned int, char const*, unsigned int, unsigned long long, unsigned long long, unsigned long long, unsigned int, unsigned long long, unsigned short, char const*, unsigned int, unsigned int, unsigned short, unsigned short, int const*) (/mp4box/mp4fragment/mp4fragment+0x6ec0c2)
    #3 0x432bbc in main (/mp4box/mp4fragment/mp4fragment+0x432bbc)
    #4 0x7f5fc1330c86 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21c86)
    #5 0x407cd9 in _start (/mp4box/mp4fragment/mp4fragment+0x407cd9)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV (/lib/x86_64-linux-gnu/libc.so.6+0xb1306) 
==750986==ABORTING

```
# POC
[POC-Mp4fragment-1.zip](https://github.com/axiomatic-systems/Bento4/files/9617496/POC-Mp4fragment-1.zip)


# Environment

Ubuntu 18.04.6 LTS (docker)
clang 12.0.1
clang++ 12.0.1
Bento4 master branch(5b7cc25) && Bento4 release version([1.6.0-639](https://www.bok.net/Bento4/binaries/Bento4-SDK-1-6-0-639.x86_64-unknown-linux.zip))


# Credit
Xudong Cao ([NCNIPC of China](http://www.nipc.org.cn/)), (Zhongguancun Laboratory)
Jiayuan Zhang ([NCNIPC of China](http://www.nipc.org.cn/)), (Zhongguancun Laboratory)
Han Zheng ([NCNIPC of China](http://www.nipc.org.cn/), [Hexhive](http://hexhive.epfl.ch/))

Thank you for your time!

--- end body ---

A segmentation fault (SEGV) in the mp4fragment binary of Bento4 indicates a potential vulnerability that can be exploited through crafted input files. The crash occurs due to a read access violation, specifically when the program attempts to read from a null pointer, which can lead to undefined behavior and potential exploitation.