Commit: patch 9.2.0678: [security]: potential powershell code execution in zip.vim

[Christian Brabandt]

patch 9.2.0678: [security]: potential powershell code execution in zip.vim

Commit: https://github.com/vim/vim/commit/b2cc9be119d51212bf0d3f2a994c7e517c73f4a9
Author: Christian Brabandt <c...@256bit.org>
Date: Sat Jun 20 15:35:58 2026 +0000

patch 9.2.0678: [security]: potential powershell code execution in zip.vim

Problem: [security]: potential powershell code execution in zip.vim
(DDugs)
Solution: Cleanup zip.vim, introduce PSEscape() to escape() potential powershell code,
use consistent s:Escape() in the various PowerShell functions

Github Security Advisory:
https://github.com/vim/vim/security/advisories/GHSA-x5fg-h5w9-9frf

Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/runtime/autoload/zip.vim b/runtime/autoload/zip.vim
index aad548239..44bdfc682 100644
--- a/runtime/autoload/zip.vim
+++ b/runtime/autoload/zip.vim
@@ -24,6 +24,7 @@
" 2026 Apr 05 by Vim Project: Detect more path traversal attacks
" 2026 Apr 14 by Vim Project: Detect more path traversal attacks on Windows
" 2026 Apr 15 by Vim Project: Detect more path traversal attacks on Windows
+" 2026 Jun 20 by Vim Project: Fix wrong escaping for the powershell calls
" License: Vim License (see vim's :help license)
" Copyright: Copyright (C) 2005-2019 Charles E. Campbell {{{1
" Permission is hereby granted to use and distribute this code,
@@ -51,15 +52,6 @@ let s:NOTE = 0

" ---------------------------------------------------------------------
" Global Values: {{{1
-if !exists("g:zip_shq")
- if &shq != ""
- let g:zip_shq= &shq
- elseif has("unix")
- let g:zip_shq= "'"
- else
- let g:zip_shq= '"'
- endif
-endif
if !exists("g:zip_zipcmd")
let g:zip_zipcmd= "zip"
endif
@@ -135,7 +127,7 @@ function! s:ZipBrowsePS(zipfile)
" Browse the contents of a zip file using PowerShell's
" Equivalent `unzip -Z1 -- zipfile`
let cmds = [
- \ '$zip = [System.IO.Compression.ZipFile]::OpenRead(' . s:Escape(a:zipfile, 1) . ');',
+ \ '$zip = [System.IO.Compression.ZipFile]::OpenRead(' . s:PSEscape(a:zipfile) . ');',
\ '$zip.Entries | ForEach-Object { $_.FullName };',
\ '$zip.Dispose()'
\ ]
@@ -149,16 +141,16 @@ function! s:ZipReadPS(zipfile, fname, tempfile)
call s:Mess('WarningMsg', "***warning*** PowerShell can display, but cannot update, files in archive subfolders")
endif
let cmds = [
- \ '$zip = [System.IO.Compression.ZipFile]::OpenRead(' . s:Escape(a:zipfile, 1) . ');',
- \ '$fileEntry = $zip.Entries | Where-Object { $_.FullName -eq ' . s:Escape(a:fname, 1) . ' };',
+ \ '$zip = [System.IO.Compression.ZipFile]::OpenRead(' . s:PSEscape(a:zipfile) . ');',
+ \ '$fileEntry = $zip.Entries | Where-Object { $_.FullName -eq ' . s:PSEscape(a:fname) . ' };',
\ '$stream = $fileEntry.Open();',
- \ '$fileStream = [System.IO.File]::Create(' . s:Escape(a:tempfile, 1) . ');',
+ \ '$fileStream = [System.IO.File]::Create(' . s:PSEscape(a:tempfile) . ');',
\ '$stream.CopyTo($fileStream);',
\ '$fileStream.Close();',
\ '$stream.Close();',
\ '$zip.Dispose()'
\ ]
- return 'pwsh -NoProfile -Command ' . s:Escape(join(cmds, ' '), 1)
+ return 'pwsh -NoProfile -Command ' . s:Escape(join(cmds, ' '))
endfunction

function! s:ZipUpdatePS(zipfile, fname)
@@ -168,7 +160,7 @@ function! s:ZipUpdatePS(zipfile, fname)
call s:Mess('Error', "***error*** PowerShell cannot update files in archive subfolders")
return ':'
endif
- return 'Compress-Archive -Path ' . a:fname . ' -Update -DestinationPath ' . a:zipfile
+ return 'Compress-Archive -Path ' . s:PSEscape(a:fname) . ' -Update -DestinationPath ' . s:PSEscape(a:zipfile)
endfunction

function! s:ZipExtractFilePS(zipfile, fname)
@@ -179,16 +171,16 @@ function! s:ZipExtractFilePS(zipfile, fname)
return ':'
endif
let cmds = [
- \ '$zip = [System.IO.Compression.ZipFile]::OpenRead(' . s:Escape(a:zipfile, 1) . ');',
- \ '$fileEntry = $zip.Entries | Where-Object { $_.FullName -eq ' . a:fname . ' };',
+ \ '$zip = [System.IO.Compression.ZipFile]::OpenRead(' . s:PSEscape(a:zipfile) . ');',
+ \ '$fileEntry = $zip.Entries | Where-Object { $_.FullName -eq ' . s:PSEscape(a:fname) . ' };',
\ '$stream = $fileEntry.Open();',
- \ '$fileStream = [System.IO.File]::Create(' . a:fname . ');',
+ \ '$fileStream = [System.IO.File]::Create(' . s:PSEscape(a:fname) . ');',
\ '$stream.CopyTo($fileStream);',
\ '$fileStream.Close();',
\ '$stream.Close();',
\ '$zip.Dispose()'
\ ]
- return 'pwsh -NoProfile -Command ' . s:Escape(join(cmds, ' '), 1)
+ return 'pwsh -NoProfile -Command ' . s:Escape(join(cmds, ' '))
endfunction

function! s:ZipDeleteFilePS(zipfile, fname)
@@ -196,12 +188,12 @@ function! s:ZipDeleteFilePS(zipfile, fname)
" Equivalent to `zip -d zipfile fname`
let cmds = [
\ 'Add-Type -AssemblyName System.IO.Compression.FileSystem;',
- \ '$zip = [System.IO.Compression.ZipFile]::Open(' . s:Escape(a:zipfile, 1) . ', ''Update'');',
- \ '$entry = $zip.Entries | Where-Object { $_.Name -eq ' . s:Escape(a:fname, 1) . ' };',
+ \ '$zip = [System.IO.Compression.ZipFile]::Open(' . s:PSEscape(a:zipfile) . ', ''Update'');',
+ \ '$entry = $zip.Entries | Where-Object { $_.Name -eq ' . s:PSEscape(a:fname) . ' };',
\ 'if ($entry) { $entry.Delete(); $zip.Dispose() }',
\ 'else { $zip.Dispose() }'
\ ]
- return 'pwsh -NoProfile -Command ' . s:Escape(join(cmds, ' '), 1)
+ return 'pwsh -NoProfile -Command ' . s:Escape(join(cmds, ' '))
endfunction

" ----------------
@@ -341,9 +333,9 @@ fun! zip#Read(fname,mode)
let temp = tempname()
let fn = expand('%:p')

- let gnu_cmd = g:zip_unzipcmd . ' -p -- ' . s:Escape(zipfile, 0) . ' ' . s:Escape(fname, 0) . ' > ' . s:Escape(temp, 0)
- let gnu_cmd = 'call system(''' . substitute(gnu_cmd, "'", "''", 'g') . ''')'
- let ps_cmd = 'sil !' . s:ZipReadPS(zipfile, fname, temp)
+ let gnu_cmd = g:zip_unzipcmd . ' -p -- ' . s:Escape(zipfile) . ' ' . s:Escape(fname) . ' > ' . s:Escape(temp)
+ let gnu_cmd = 'call system(' . string(gnu_cmd) . ')'
+ let ps_cmd = 'call system(' . string(s:ZipReadPS(zipfile, fname, temp)) . ')'
call s:TryExecGnuFallBackToPs(g:zip_unzipcmd, gnu_cmd, ps_cmd)

sil exe 'keepalt file '.temp
@@ -415,9 +407,9 @@ fun! zip#Write(fname)
endif
endif
if fname =~ '^[.]\{1,2}/'
- let gnu_cmd = g:zip_zipcmd . ' -d ' . s:Escape(fnamemodify(zipfile,":p"),0) . ' ' . s:Escape(fname,0)
- let gnu_cmd = 'call system(''' . substitute(gnu_cmd, "'", "''", 'g') . ''')'
- let ps_cmd = $"call system({s:Escape(s:ZipDeleteFilePS(zipfile, fname), 1)})"
+ let gnu_cmd = g:zip_zipcmd . ' -d ' . s:Escape(fnamemodify(zipfile,":p")) . ' ' . s:Escape(fname)
+ let gnu_cmd = 'call system(' . string(gnu_cmd) . ')'
+ let ps_cmd = $"call system({string(s:ZipDeleteFilePS(zipfile, fname))})"
call s:TryExecGnuFallBackToPs(g:zip_zipcmd, gnu_cmd, ps_cmd)
let fname = fname->substitute('^\([.]\{1,2}/\)\+', '', 'g')
let need_rename = 1
@@ -426,7 +418,7 @@ fun! zip#Write(fname)
if fname =~ '/'
let dirpath = substitute(fname,'/[^/]\+$','','e')
if has("win32unix") && executable("cygpath")
- let dirpath = substitute(system("cygpath ".s:Escape(dirpath,0)),'
','','e')
+ let dirpath = substitute(system("cygpath ".s:Escape(dirpath)),'
','','e')
endif
call mkdir(dirpath,"p")
endif
@@ -437,16 +429,17 @@ fun! zip#Write(fname)
" don't overwrite files forcefully
exe "w ".fnameescape(fname)
if has("win32unix") && executable("cygpath")
- let zipfile = substitute(system("cygpath ".s:Escape(zipfile,0)),'
','','e')
+ let zipfile = substitute(system("cygpath ".s:Escape(zipfile)),'
','','e')
endif

if (has("win32") || has("win95") || has("win64") || has("win16")) && &shell !~? 'sh$'
let fname = substitute(fname, '[', '[[]', 'g')
endif

- let gnu_cmd = g:zip_zipcmd . ' -u '. s:Escape(fnamemodify(zipfile,":p"),0) . ' ' . s:Escape(fname,0)
+ let gnu_cmd = g:zip_zipcmd . ' -u '. s:Escape(fnamemodify(zipfile,":p")) . ' ' . s:Escape(fname)
let gnu_cmd = 'call system(''' . substitute(gnu_cmd, "'", "''", 'g') . ''')'
- let ps_cmd = s:ZipUpdatePS(s:Escape(fnamemodify(zipfile, ':p'), 0), s:Escape(fname, 0))
+ let zip = fnamemodify(zipfile, ':p')
+ let ps_cmd = s:ZipUpdatePS(zip, fname)
let ps_cmd = 'call system(''' . substitute(ps_cmd, "'", "''", 'g') . ''')'
call s:TryExecGnuFallBackToPs(g:zip_zipcmd, gnu_cmd, ps_cmd)
if &shell =~ 'pwsh'
@@ -541,8 +534,8 @@ fun! zip#Extract()

" extract the file mentioned under the cursor
let gnu_cmd = g:zip_extractcmd . ' -o '. shellescape(b:zipfile) . ' ' . target
- let gnu_cmd = 'call system(''' . substitute(gnu_cmd, "'", "''", 'g') . ''')'
- let ps_cmd = $"call system({s:Escape(s:ZipExtractFilePS(b:zipfile, target), 1)})"
+ let gnu_cmd = 'call system(' . string(gnu_cmd) . ')'
+ let ps_cmd = 'call system(' . string(s:ZipExtractFilePS(b:zipfile, fname)) . ')'
call s:TryExecGnuFallBackToPs(g:zip_extractcmd, gnu_cmd, ps_cmd)

if v:shell_error != 0
@@ -556,19 +549,20 @@ endfun

" ---------------------------------------------------------------------
" s:Escape: {{{2
-fun! s:Escape(fname,isfilt)
- if exists("*shellescape")
- if a:isfilt
- let qnameq= shellescape(a:fname,1)
- else
- let qnameq= shellescape(a:fname)
- endif
+fun! s:Escape(fname, isfilt = 0)
+ if a:isfilt
+ let qnameq = shellescape(a:fname, 1)
else
- let qnameq= g:zip_shq.escape(a:fname,g:zip_shq).g:zip_shq
+ let qnameq = shellescape(a:fname)
endif
return qnameq
endfun

+" s:PSEscape: Escape a string for Powershell, shellescape() does not work here {{{2
+fun! s:PSEscape(str)
+ return "'" .. substitute(a:str, "'", "''", 'g') .. "'"
+endfun
+
" ---------------------------------------------------------------------
" s:ChgDir: {{{2
fun! s:ChgDir(newdir,errlvl,errmsg)
diff --git a/runtime/doc/pi_zip.txt b/runtime/doc/pi_zip.txt
index 81275b24e..dc462cfef 100644
--- a/runtime/doc/pi_zip.txt
+++ b/runtime/doc/pi_zip.txt
@@ -1,4 +1,4 @@
-*pi_zip.txt* For Vim version 9.2. Last change: 2026 May 16
+*pi_zip.txt* For Vim version 9.2. Last change: 2026 Jun 20

+====================+
| Zip File Interface |
@@ -48,16 +48,6 @@ Copyright: Copyright (C) 2005-2015 Charles E Campbell *zip-copyright*
If this variable exists and is true, the file window will not be
automatically maximized when opened.

- *g:zip_shq*
- Different operating systems may use one or more shells to execute
- commands. Zip will try to guess the correct quoting mechanism to
- allow spaces and whatnot in filenames; however, if it is incorrectly
- guessing the quote to use for your setup, you may use >
- g:zip_shq
-< which by default is a single quote under Unix (') and a double quote
- under Windows ("). If you'd rather have no quotes, simply set
- g:zip_shq to the empty string (let g:zip_shq= "") in your <.vimrc>.
-
*g:zip_unzipcmd*
Use this option to specify the program which does the duty of "unzip".
It's used during browsing. By default: >
diff --git a/src/version.c b/src/version.c
index d2e01aecb..9de098d71 100644
--- a/src/version.c
+++ b/src/version.c
@@ -759,6 +759,8 @@ static char *(features[]) =

static int included_patches[] =
{ /* Add new patch number below this line */
+/**/
+ 678,
/**/
677,
/**/