delorie.com/archives/browse.cgi   search  
Mail Archives: cygwin/2018/02/13/22:25:56

X-Recipient: archive-cygwin AT delorie DOT com
DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id
:list-unsubscribe:list-subscribe:list-archive:list-post
:list-help:sender:reply-to:subject:to:references:from:message-id
:date:mime-version:in-reply-to:content-type; q=dns; s=default; b=
er3rDfLr4ZBpgEkwcGaYleA7emWuZhmeyB7viRBoIPv7co0cLLHttwP8FqD8q9nw
dSKy4lqdDZ6AyH+imtOU6LiZHUgZPl+MGV7WY2cOxIqHj9irU+u0T/hYV/EuyPPm
5hLJbC5w97+b9coUlWqfyz5y188IZ5aQXvNd3Ig2W4w=
DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id
:list-unsubscribe:list-subscribe:list-archive:list-post
:list-help:sender:reply-to:subject:to:references:from:message-id
:date:mime-version:in-reply-to:content-type; s=default; bh=bEyfc
aXe0yrnvPVzOrfynCbbeWs=; b=jLhFZ12PN7PPaqhKPpNgh+t7PU8gSBu5Bmn+7
SFb0rPyhBljq0hPw8mNh6j9O0FVNmAfcY3A/BMbDxlm2cZqclmNW6C0Z147XQ700
aPfYnAR63m/DUQoFMotM5tG4fhI0DianatCmI02ROuoIVgUTu7C5+VidxsmT8aBm
gEr+a0=
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id: <cygwin.cygwin.com>
List-Subscribe: <mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive: <http://sourceware.org/ml/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Delivered-To: mailing list cygwin AT cygwin DOT com
Authentication-Results: sourceware.org; auth=none
X-Virus-Found: No
X-Spam-SWARE-Status: No, score=-1.8 required=5.0 tests=AWL,BAYES_00,KAM_LAZY_DOMAIN_SECURITY,RCVD_IN_DNSWL_LOW autolearn=no version=3.3.2 spammy=sk:systems, threat, UD:blogs.technet.microsoft.com, blogs.technet.microsoft.com
X-HELO: smtp-out-so.shaw.ca
X-Authority-Analysis: v=2.3 cv=D6Jp1MZj c=1 sm=1 tr=0 a=MVEHjbUiAHxQW0jfcDq5EA==:117 a=MVEHjbUiAHxQW0jfcDq5EA==:17 a=r77TgQKjGQsHNAKrUKIA:9 a=yMhMjlubAAAA:8 a=w_pzkKWiAAAA:8 a=DebnMqUAnOt0llDUNdoA:9 a=7Zwj6sZBwVKJAoWSPKxL6X1jA+E=:19 a=pILNOxqGKmIA:10 a=uxdnVy1cKkYA:10 a=nFIw9-zvy9kA:10 a=FFmbRamVujO-ixZxrPMA:9 a=zJJgJrR4LD4A:10 a=jvwAycmo3Y0A:10 a=sRI3_1zDfAgwuvI8zelB:22
Reply-To: Brian DOT Inglis AT SystematicSw DOT ab DOT ca
Subject: Re: W10 Mandatory ASLR default (was: cygwin stopped working)
To: cygwin AT cygwin DOT com
References: <8297ddf5-5d06-c2b1-526b-16ca311749aa AT ferzkopp DOT net> <CAJ1FpuMivfg+RKg3kDf8rt6n-Ky0Ami_5_HpGjbAMGpHgM57Tg AT mail DOT gmail DOT com> <e4b6f4cd-1fb2-5d4c-1f94-f8ca73bbfa1f AT ferzkopp DOT net> <20180212164945 DOT GA2361 AT jbsupah> <ec5eb9a0-b33e-5bc8-090d-db0c571d5846 AT ferzkopp DOT net>
From: Brian Inglis <Brian DOT Inglis AT SystematicSw DOT ab DOT ca>
Message-ID: <dd3a6a82-19bb-eb84-51df-5d1cde39315f@SystematicSw.ab.ca>
Date: Tue, 13 Feb 2018 20:25:39 -0700
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0
MIME-Version: 1.0
In-Reply-To: <ec5eb9a0-b33e-5bc8-090d-db0c571d5846@ferzkopp.net>
X-CMAE-Envelope: MS4wfJwIyrjklXnVssFfDHhxcK9KxqBcRLFpVZeIwa9SBHineW5DANrLZzVgLyftZUf3jwpR2qYtqDgRVzeg31W4y6RAfJC1a1CHZlcmEriwS0J6/BFIrlU0 IxXtvhW8Q4oiiNlNdSUY2VGeKx51KzB7NVKj6MFGjqVbDT+YEtKl0vdQmjfQVuIEOToMdzkAhuQ7hA==
X-IsSubscribed: yes

--------------85D95F6EAC2BF17F8DFBA3D8
Content-Type: text/plain; charset=windows-1252
Content-Transfer-Encoding: 7bit

On 2018-02-12 21:58, Andreas Schiffler wrote:
> Found the workaround (read: not really a solution as it leaves the system
> vulnerable, but it unblocks cygwin)
> - Go to Windows Defender Security Center - Exploit protection settings
> - Disable System Settings - Force randomization for images (Mandatory ASLR) and
> Randomize memory allocations (Bottom-up ASLR) from "On by default" to "Off by
> default"
> 
> Now setup.exe works and can rebase everything; after that Cygwin Terminal starts
> as a working shell without problems.
> 
> @cygwin dev's - It seems one of the windows updates (system is on 1709 build
> 16299.214) might have changed my ASLR settings to "system wide mandatory" (i.e.
> see
> https://blogs.technet.microsoft.com/srd/2017/11/21/clarifying-the-behavior-of-mandatory-aslr/
> for info) so that the cygwin DLLs don't work correctly anymore (i.e. see old 
> thread about this topic here
> https://www.cygwin.com/ml/cygwin/2013-06/msg00092.html). 
> This change might have made it into the system as part of the security update
> for Meltdown+Spectre (I am speculating), but that could explain why my cygwin
> installation that worked fine before (i.e. mid-2017) stopped working suddenly
> (beginning 2018). It would be good to devize a test for the setup.exe that
> checks the registry (likely
> [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\kernel])
> for this state and alerts the user.
I'm on W10 Home 1709/16299.192 (slightly older).

Under Windows Defender Security Center/App & browser control/Exploit
protection/Exploit protection settings/System settings/Force randomization for
images (Mandatory ASLR) - "Force relocation of images not compiled with
/DYNAMICBASE" is "Off by default", whereas Randomize memory allocations
(Bottom-up ASLR) - "Randomize locations for virtual memory allocations." and all
other settings are "On by default".

Under Windows Defender Security Center/App & browser control/Exploit
protection/Exploit protection settings/Program settings various .exes have 0-2
system overrides of settings.

I used the Export settings selection at the bottom to export the settings, which
use the implied System settings defaults, and include the Program settings
system overrides shown in the attached xml file.

It may be useful if you could export your default and updated settings for
comparison and information.
It would be nice if one of the project volunteers with Windows threat mitigation
knowledge could look at these, to see if there is a better approach.

I expect to get updated the next time I restart, as I have been seeing
notifications to that effect, and will not be surprised if my system startup
Cygwin shell scripts fail.

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

--------------85D95F6EAC2BF17F8DFBA3D8
Content-Type: text/xml;
 name="ExploitProtectionProgramSettingsSystemOverrides.xml"
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment;
 filename*0="ExploitProtectionProgramSettingsSystemOverrides.xml"

<?xml version="1.0" encoding="UTF-8"?>
<root>
  <SystemConfig></SystemConfig>
  <AppConfig Executable="DevicesFlow.exe">
    <ExtensionPoints DisableExtensionPoints="true" OverrideExtensionPoint="false"></ExtensionPoints>
  </AppConfig>
  <AppConfig Executable="ExtExport.exe">
    <ASLR Enable="true" ForceRelocateImages="false" OverrideForceRelocateImages="false"></ASLR>
  </AppConfig>
  <AppConfig Executable="ie4uinit.exe">
    <ASLR Enable="true" ForceRelocateImages="false" OverrideForceRelocateImages="false"></ASLR>
  </AppConfig>
  <AppConfig Executable="ieinstal.exe">
    <ASLR Enable="true" ForceRelocateImages="false" OverrideForceRelocateImages="false"></ASLR>
  </AppConfig>
  <AppConfig Executable="ielowutil.exe">
    <ASLR Enable="true" ForceRelocateImages="false" OverrideForceRelocateImages="false"></ASLR>
  </AppConfig>
  <AppConfig Executable="ieUnatt.exe">
    <ASLR Enable="true" ForceRelocateImages="false" OverrideForceRelocateImages="false"></ASLR>
  </AppConfig>
  <AppConfig Executable="iexplore.exe">
    <ASLR Enable="true" ForceRelocateImages="false" OverrideForceRelocateImages="false"></ASLR>
  </AppConfig>
  <AppConfig Executable="MiracastView.exe">
    <ExtensionPoints DisableExtensionPoints="true" OverrideExtensionPoint="false"></ExtensionPoints>
  </AppConfig>
  <AppConfig Executable="mscorsvw.exe">
    <ExtensionPoints DisableExtensionPoints="true" OverrideExtensionPoint="false"></ExtensionPoints>
  </AppConfig>
  <AppConfig Executable="msfeedssync.exe">
    <ASLR Enable="true" ForceRelocateImages="false" OverrideForceRelocateImages="false"></ASLR>
  </AppConfig>
  <AppConfig Executable="mshta.exe">
    <ASLR Enable="true" ForceRelocateImages="false" OverrideForceRelocateImages="false"></ASLR>
  </AppConfig>
  <AppConfig Executable="ngen.exe">
    <ExtensionPoints DisableExtensionPoints="true" OverrideExtensionPoint="false"></ExtensionPoints>
  </AppConfig>
  <AppConfig Executable="ngentask.exe">
    <ExtensionPoints DisableExtensionPoints="true" OverrideExtensionPoint="false"></ExtensionPoints>
  </AppConfig>
  <AppConfig Executable="PresentationHost.exe">
    <DEP Enable="true" EmulateAtlThunks="false" OverrideDEP="false"></DEP>
    <ASLR Enable="true" ForceRelocateImages="false" OverrideForceRelocateImages="false" BottomUp="true" HighEntropy="true" OverrideBottomUp="false"></ASLR>
    <SEHOP Enable="true" TelemetryOnly="false" OverrideSEHOP="false"></SEHOP>
    <Heap TerminateOnError="true" OverrideHeap="false"></Heap>
  </AppConfig>
  <AppConfig Executable="PrintDialog.exe">
    <ExtensionPoints DisableExtensionPoints="true" OverrideExtensionPoint="false"></ExtensionPoints>
  </AppConfig>
  <AppConfig Executable="PrintIsolationHost.exe"></AppConfig>
  <AppConfig Executable="runtimebroker.exe">
    <ExtensionPoints DisableExtensionPoints="true" OverrideExtensionPoint="false"></ExtensionPoints>
  </AppConfig>
  <AppConfig Executable="splwow64.exe"></AppConfig>
  <AppConfig Executable="spoolsv.exe"></AppConfig>
  <AppConfig Executable="svchost.exe"></AppConfig>
  <AppConfig Executable="SystemSettings.exe">
    <ExtensionPoints DisableExtensionPoints="true" OverrideExtensionPoint="false"></ExtensionPoints>
  </AppConfig>
</root>

--------------85D95F6EAC2BF17F8DFBA3D8
Content-Type: text/plain; charset=us-ascii


--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
--------------85D95F6EAC2BF17F8DFBA3D8--

- Raw text -


  webmaster     delorie software   privacy  
  Copyright © 2019   by DJ Delorie     Updated Jul 2019