fix(lib): fix potential command injection in title and spectrum functions

The `title` function unsafely prints its input without sanitization, which if used
with custom user code that calls it, it could trigger command injection.

The `spectrum_ls` and `spectrum_bls` could similarly be exploited if a variable is
changed in the user's shell environment with a carefully crafted value. This is
highly unlikely to occur (and if possible, other methods would be used instead),
but with this change the exploit of these two functions is now impossible.
This commit is contained in:
Marc Cornellà 2021-11-09 09:08:18 +01:00
parent 06fc5fb129
commit a263cdac9c
No known key found for this signature in database
GPG key ID: 0314585E776A9C1B
2 changed files with 10 additions and 9 deletions

View file

@ -20,16 +20,18 @@ done
# Show all 256 colors with color number # Show all 256 colors with color number
function spectrum_ls() { function spectrum_ls() {
setopt localoptions nopromptsubst
local ZSH_SPECTRUM_TEXT=${ZSH_SPECTRUM_TEXT:-Arma virumque cano Troiae qui primus ab oris} local ZSH_SPECTRUM_TEXT=${ZSH_SPECTRUM_TEXT:-Arma virumque cano Troiae qui primus ab oris}
for code in {000..255}; do for code in {000..255}; do
print -P -- "$code: $FG[$code]$ZSH_SPECTRUM_TEXT%{$reset_color%}" print -P -- "$code: ${FG[$code]}${ZSH_SPECTRUM_TEXT}%{$reset_color%}"
done done
} }
# Show all 256 colors where the background is set to specific color # Show all 256 colors where the background is set to specific color
function spectrum_bls() { function spectrum_bls() {
setopt localoptions nopromptsubst
local ZSH_SPECTRUM_TEXT=${ZSH_SPECTRUM_TEXT:-Arma virumque cano Troiae qui primus ab oris} local ZSH_SPECTRUM_TEXT=${ZSH_SPECTRUM_TEXT:-Arma virumque cano Troiae qui primus ab oris}
for code in {000..255}; do for code in {000..255}; do
print -P -- "$code: $BG[$code]$ZSH_SPECTRUM_TEXT%{$reset_color%}" print -P -- "$code: ${BG[$code]}${ZSH_SPECTRUM_TEXT}%{$reset_color%}"
done done
} }

View file

@ -7,8 +7,7 @@
# (In screen, only short_tab_title is used) # (In screen, only short_tab_title is used)
# Limited support for Apple Terminal (Terminal can't set window and tab separately) # Limited support for Apple Terminal (Terminal can't set window and tab separately)
function title { function title {
emulate -L zsh setopt localoptions nopromptsubst
setopt prompt_subst
# Don't set the title if inside emacs, unless using vterm # Don't set the title if inside emacs, unless using vterm
[[ -n "$INSIDE_EMACS" && "$INSIDE_EMACS" != vterm ]] && return [[ -n "$INSIDE_EMACS" && "$INSIDE_EMACS" != vterm ]] && return
@ -48,13 +47,13 @@ fi
# Runs before showing the prompt # Runs before showing the prompt
function omz_termsupport_precmd { function omz_termsupport_precmd {
[[ "${DISABLE_AUTO_TITLE:-}" == true ]] && return [[ "${DISABLE_AUTO_TITLE:-}" != true ]] || return
title $ZSH_THEME_TERM_TAB_TITLE_IDLE $ZSH_THEME_TERM_TITLE_IDLE title "$ZSH_THEME_TERM_TAB_TITLE_IDLE" "$ZSH_THEME_TERM_TITLE_IDLE"
} }
# Runs before executing the command # Runs before executing the command
function omz_termsupport_preexec { function omz_termsupport_preexec {
[[ "${DISABLE_AUTO_TITLE:-}" == true ]] && return [[ "${DISABLE_AUTO_TITLE:-}" != true ]] || return
emulate -L zsh emulate -L zsh
setopt extended_glob setopt extended_glob
@ -97,10 +96,10 @@ function omz_termsupport_preexec {
fi fi
# cmd name only, or if this is sudo or ssh, the next cmd # cmd name only, or if this is sudo or ssh, the next cmd
local CMD=${1[(wr)^(*=*|sudo|ssh|mosh|rake|-*)]:gs/%/%%} local CMD="${1[(wr)^(*=*|sudo|ssh|mosh|rake|-*)]:gs/%/%%}"
local LINE="${2:gs/%/%%}" local LINE="${2:gs/%/%%}"
title '$CMD' '%100>...>$LINE%<<' title "$CMD" "%100>...>${LINE}%<<"
} }
autoload -Uz add-zsh-hook autoload -Uz add-zsh-hook