If you want some more interesting seg faults, here are some: 1)
bash-5.1$ (\${_@P};${_@P}) Segmentation fault (core dumped) # golfed version of p='${p@P}'; : "${p@P}" bash-5.1$ bash --norc bash-5.1$ PS1=\${PS1@P} Segmentation fault (core dumped) bash-5.1$ # in an interactive shell, PS1='${PS1@P}' will also cause a crash # when PS1 is implictly expanded before being printed 2) bash-5.1$ (eval "$BASH_COMMAND"') Segmentation fault (core dumped) 3) bash-5.1$ gcc -shared -xc -ocool_builtin - <<< 'int cool_struct=0;' bash-5.1$ (enable -f ./cool_builtin cool) Segmentation fault (core dumped) 4) bash-5.1$ (_[\${!_}];$[_]) Segmentation fault (core dumped) # golfed version of x='x[${!x}]'; : "$(( x ))" # may also be triggered using x='x[${!x}]'; : "${!x}" # or by using a builtin that takes a varname: # *) x='x[${!x}]'; read -r "$x" <<< '' # *) x='x[${!x}]'; printf -v "$x" '' # *) x='x[${!x}]'; [ -v "$x" ] # *) ... Cheers. emanuele6 On 31/08/2022, Евгений Штанов <evg.shta...@gmail.com> wrote: > Configuration Information [Automatically generated, do not change]: > Machine: x86_64 > OS: linux-gnu > Compiler: gcc > Compilation CFLAGS: -g -O2 -flto=auto -ffat-lto-objects -flto=auto > -ffat-lto-objects -fstack-protector-strong -Wformat -Werror=format-security > -Wall > uname output: Linux Shtanov-Home-PC 5.10.16.3-microsoft-standard-WSL2 #1 > SMP Fri Apr 2 22:23:49 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux > Machine Type: x86_64-pc-linux-gnu > > Bash Version: 5.1 > Patch Level: 16 > Release Status: release > > Description: > Hi! I was fuzzing bash with AFL++ and found segmentation fault. > Backtrace in in attachment > > Repeat-By: > 1. Build bash; > 2. Run with AFL++ crafted input (in attachment). >