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@tophf
Last active December 1, 2025 01:13
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Enables ManifestV2 for extensions in Chrome 140+
<# 1. To patch dll in a protected folder like "c:\program files" run this script as Administrator.
2. If your Windows isn't configured to run ps1 files, you can run it from command prompt like this:
powershell -ep bypass -noprofile "patch-chrome-mv2.ps1"
#>
param([string]$dll, [string]$dir = $pwd)
function doPatch([string]$path, [string]$pathLabel = '') {
$dll = $script:dll = if ($path.EndsWith('\')) { Join-Path $path chrome.dll } else { $path }
if (!(Test-Path -literal $dll)) { return }
$localAppData = [Environment]::GetFolderPath('LocalApplicationData')
write-host -f yellow "`n$(@($pathLabel, (split-path $dll).Replace($localAppData, '%LocalAppData%')) -join ' ')"
$script:stream = [IO.File]::Open($dll, [IO.FileMode]::Open, [IO.FileAccess]::Read, [IO.FileShare]::ReadWrite)
$reader = [IO.BinaryReader]$stream
$enc = [Text.Encoding]::GetEncoding(28591)
$features = @(
'-ExtensionManifestV2Unsupported'
'-ExtensionManifestV2Disabled'
'-ExtensionsManifestV3Only'
'+AllowLegacyMV2Extensions'
)
write-host -f DarkGray "`tREADING Chrome.dll..."
[void]$stream.seek(0x3C, 0)
$coff = $reader.ReadUint32() + 4
$coffSize = 20
[void]$stream.seek($coff, 0)
$bytes = $reader.ReadBytes($coffSize + 2)
$is64 = [BitConverter]::ToUInt16($bytes, 0) -eq 0x8664
$isPE32 = [BitConverter]::ToUInt16($bytes, $coffSize) -eq 0x010b
[void]$stream.seek($coff + $coffSize + 24 + 4 * $isPE32, 0)
$imageBase = if ($isPE32) { $reader.ReadUInt32() } else { $reader.ReadUInt64() }
# find sections
$extraHeaderSize = [BitConverter]::ToUInt16($bytes, 16)
$numSections = [BitConverter]::ToUInt16($bytes, 2)
[void]$stream.seek($coff + $coffSize + $extraHeaderSize, 0)
$sections = @{}
foreach ($i in 1..$numSections) {
$sec = $reader.ReadBytes(40)
$i = $sec.IndexOf([byte]0)
$name = $enc.GetString($sec, 0, $(if ($i -lt 0) { 8 } else { [math]::min(8, $i) }))
if ($name -eq '.rdata' -or $name -eq '.data') {
$sections[$name.substring(1)] = @{
addr = $imageBase + [uint64][BitConverter]::ToUInt32($sec, 12);
size = [BitConverter]::ToUInt32($sec, 16);
filePos = [BitConverter]::ToUInt32($sec, 20);
}
if ($sections.count -eq 2) { break }
}
}
# .rdata section
if (!$sections.rdata) {
return "Could not find .rdata section"
}
[void]$stream.seek($sections.rdata.filePos, 0)
$cur = 0
$step = 1MB
$featArea = 1kB
$featData = [ordered]@{}
while ($cur -lt $sections.rdata.size) {
$bytes = $reader.ReadBytes($step)
$str = $enc.GetString($bytes)
foreach ($feat in $features) {
if ($featData[$feat]) { continue }
$pos = $str.indexOf($feat.substring(1))
if ($pos -lt 0) { break }
$featData[$feat] = $sections.rdata.addr + $cur + $pos
}
if ($featData.count -eq $features.length) { break }
$cur += $step - $featArea
[void]$stream.seek(-$featArea, [IO.SeekOrigin]::Current)
}
if (!$sections.data) {
return "Could not find .data section"
}
# .data section
[void]$stream.seek($sections.data.filePos, 0)
$len = $sections.data.size
$bytes = $reader.ReadBytes($len)
if ($is64) { $words = [uint64[]]::new($len -shr 3) }
else { $words = [uint32[]]::new($len -shr 2) }
[Buffer]::BlockCopy($bytes, 0, $words, 0, $len)
$bytes = $null
$copied = $false
$wordType = $words[0].getType()
foreach ($feat in $featData.Keys) {
$needle = $featData[$feat]
$needle = $needle -as $wordType
$val = ($feat[0] -eq '+') -as $wordType
$feat = $feat.substring(1)
$i = $words.indexOf($needle)
while ($i -ge 0 -and !($words[$i + 1] -in 0,1)) {
$i = [Array]::IndexOf($words, $needle, $i + 1)
}
if (!++$i) {
return "Could not find $feat pointer in .data section"
}
if ($words[$i] -eq $val) {
write-host -f darkcyan "`tAlready patched $feat"
continue
}
if (!$copied) {
$copied = $true
$stream.close()
$script:stream = [IO.File]::Open($dll, [IO.FileMode]::Open, [IO.FileAccess]::ReadWrite, [IO.FileShare]::Read)
if (test-path -literal "$dll.BAK") {
write-host -f darkgray "`tFound an existing backup of the original dll."
} else {
write-host -f darkgray "`tBacking up the original dll..."
[IO.File]::Copy($dll, "$dll.BAK")
}
}
write-host -f cyan "`tPatching $feat..."
[void]$stream.seek($sections.data.filePos + $i * (4 + 4 * $is64), 0)
$stream.WriteByte($val)
}
write-host -f green "`tDONE."
}
function tryPatch($a, $b) {
try {
$err = doPatch $a $b
} catch {
$a = ([regex]'\): "(.+)"').match($Error[0]).Groups[1].Value
if ($a) { $err = $a.Replace($dll, 'chrome.dll') } else { $Error[0] }
}
if ($stream) {
$stream.close()
$script:stream = $null
}
if ($err) {
write-host -f red "`t$err"
$script:err = $true
}
[GC]::Collect()
}
$err = $false
if ($dll) {
tryPatch $dll
} else {
$pathsDone = @{}
tryPatch ((gi -literal $dir).fullName + '\') 'CURRENT DIRECTORY'
('HKLM', 'HKCU') | %{
$hive = $_
('', '\Wow6432Node') | %{
$key = "${hive}:\SOFTWARE$_\Google\Update\Clients"
gci -ea silentlycontinue $key -r | gp | ?{ $_.CommandLine } | %{
$path = $_.CommandLine -replace '"(.+?\\\d+\.\d+\.\d+\.\d+\\).+', '$1'
if (!$pathsDone[$path.toLower()]) {
tryPatch $path REGISTRY
$pathsDone[$path.toLower()] = $true
}
}
}
}
}
if ($err) { read-host "Press Enter key to exit" }
@krystian3w
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krystian3w commented Nov 5, 2025

It may require a nerf of protection in the ESET Internet Security settings.

@tophf
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Author

tophf commented Nov 6, 2025

Maybe ESET allows adding this dll to exceptions the way Defender does.

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