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http://source.myrepos.branchable.com/?p=source.git;a=patch;h=40a3df21c73f1bb1b6915cc6fa503f50814664c8
This can be removed with the next release. It was modified slightly to apply
From 40a3df21c73f1bb1b6915cc6fa503f50814664c8 Mon Sep 17 00:00:00 2001
From: Paul Wise <pabs3@bonedaddy.net>
Date: Sun, 11 Feb 2018 21:57:49 +0800
Subject: [PATCH] Mitigate vulnerabilities caused by some git remotes being
able to execute code
Set GIT_PROTOCOL_FROM_USER=0 with git versions newer than 2.12.
Prevent remote websites from causing cloning of local repositories.
Manually whitelist known-safe protocols (http, https, git, ssh)
when using git versions older than 2.12.
Fixes: CVE-2018-7032
Fixes: https://bugs.debian.org/840014
Suggestions-by: Jakub Wilk <jwilk@jwilk.net>
Reported-by: Jakub Wilk <jwilk@jwilk.net>
---
webcheckout | 22 +++++++++++++++++++++-
1 file changed, 21 insertions(+), 1 deletion(-)
diff --git a/webcheckout b/webcheckout
index e98da5c..de497ba 100755
--- a/webcheckout
+++ b/webcheckout
@@ -71,6 +71,16 @@ use Getopt::Long;
use warnings;
use strict;
+# Mitigate some git remote types being dangerous
+my $git_unsafe = 1;
+my $git_version = `git --version`;
+$git_version =~ s{^git version }{};
+my ($major, $minor) = split(/\./, $git_version);
+if (int($major) >= 2 && int($minor) >= 12) {
+ $ENV{GIT_PROTOCOL_FROM_USER} = 0;
+ $git_unsafe = 0;
+}
+
# What to download.
my $url;
@@ -89,7 +99,17 @@ my $destdir;
# how to perform checkouts
my %handlers=(
- git => sub { doit("git", "clone", shift, $destdir) },
- svn => sub { doit("svn", "checkout", shift, $destdir) },
- bzr => sub { doit("bzr", "branch", shift, $destdir) },
+ git => sub {
+ my $git_url = shift;
+ # Reject unsafe URLs with older versions of git
+ # that do not already check the URL safety.
+ if ($git_unsafe && $git_url !~ m{^(?:(?:https?|git|ssh):[^:]|(?:[-_.A-Za-z0-9]+@)?[-_.A-Za-z0-9]+:(?!:|//))}) {
+ print STDERR "potentially unsafe git URL, may fail, touch local files or execute arbitrary code\n";
+ return 1;
+ }
+ # Reject cloning local directories too, webcheckout is for remote repos
+ doit(qw(git -c protocol.file.allow=user clone --), $git_url, $destdir)
+ },
+ svn => sub { doit(qw(svn checkout --), shift, $destdir) },
+ bzr => sub { doit(qw(bzr branch --), shift, $destdir) },
);
--
2.11.0
|