From 581455111c5c3f8812fb721ed41428b069fe55bd Mon Sep 17 00:00:00 2001 From: Todd Zullinger Date: Sat, 16 Apr 2022 14:35:59 -0400 Subject: [PATCH] xzgrep: arbitrary-file-write vulnerability (#2073310, CVE-2022-1271) --- sources | 1 + xz.spec | 9 +++- xzgrep-ZDI-CAN-16587.patch | 94 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 103 insertions(+), 1 deletion(-) create mode 100644 xzgrep-ZDI-CAN-16587.patch diff --git a/sources b/sources index cb43bff..1103c39 100644 --- a/sources +++ b/sources @@ -1,2 +1,3 @@ SHA512 (xz-5.2.5.tar.xz) = 59266068a51cb616eb31b67cd8f07ffeb2288d1391c61665ae2ec6814465afac80fec69248f6a2f2db45b44475af001296a99af6a32287226a9c41419173ccbb SHA512 (xz-5.2.5.tar.xz.sig) = ea0218ac25843c8b44686871fba573809618f074465ec52f5966a082aeeb5e01bd646d462a56a6af7a786e1c69a05b135a6735ad1f3be27daecf3a2f9be865a5 +SHA512 (xzgrep-ZDI-CAN-16587.patch.sig) = 527c2702cf3ff3ddee6e49feb6d2305e4e9cd786f856b25f0cb5776df1341c5a960ba54c179cb27c507011e1223baf4a10de8a546199806ff96f531f62b9f136 diff --git a/xz.spec b/xz.spec index 691d6b9..ab00323 100644 --- a/xz.spec +++ b/xz.spec @@ -15,11 +15,16 @@ Source0: https://tukaani.org/%{name}/%{name}-%{version}.tar.xz Source1: https://tukaani.org/%{name}/%{name}-%{version}.tar.xz.sig # https://tukaani.org/misc/lasse_collin_pubkey.txt Source2: gpgkey-3690C240CE51B4670D30AD1C38EE757D69184620.asc +# Signature for Patch2 +Source3: https://tukaani.org/%{name}/xzgrep-ZDI-CAN-16587.patch.sig Source100: colorxzgrep.sh Source101: colorxzgrep.csh -Patch1: xz-5.2.5-enable_CET.patch +Patch1: xz-5.2.5-enable_CET.patch +# xzgrep: arbitrary-file-write vulnerability (CVE-2022-1271) +# NOTE: Source3 contains the upstream signature for this patch +Patch2: https://tukaani.org/%{name}/xzgrep-ZDI-CAN-16587.patch URL: https://tukaani.org/%{name}/ Requires: %{name}-libs%{?_isa} = %{version}-%{release} @@ -88,6 +93,7 @@ commands that deal with the older LZMA format. %prep %{gpgverify} --keyring='%{SOURCE2}' --signature='%{SOURCE1}' --data='%{SOURCE0}' +%{gpgverify} --keyring='%{SOURCE2}' --signature='%{SOURCE3}' --data='%{PATCH2}' %autosetup -p1 @@ -163,6 +169,7 @@ LD_LIBRARY_PATH=$PWD/src/liblzma/.libs make check %changelog * Sat Apr 16 2022 Todd Zullinger - 5.2.5-9 - verify upstream GPG signature +- xzgrep: arbitrary-file-write vulnerability (#2073310, CVE-2022-1271) * Sat Jan 22 2022 Fedora Release Engineering - 5.2.5-8 - Rebuilt for https://fedoraproject.org/wiki/Fedora_36_Mass_Rebuild diff --git a/xzgrep-ZDI-CAN-16587.patch b/xzgrep-ZDI-CAN-16587.patch new file mode 100644 index 0000000..406ded5 --- /dev/null +++ b/xzgrep-ZDI-CAN-16587.patch @@ -0,0 +1,94 @@ +From 69d1b3fc29677af8ade8dc15dba83f0589cb63d6 Mon Sep 17 00:00:00 2001 +From: Lasse Collin +Date: Tue, 29 Mar 2022 19:19:12 +0300 +Subject: [PATCH] xzgrep: Fix escaping of malicious filenames (ZDI-CAN-16587). + +Malicious filenames can make xzgrep to write to arbitrary files +or (with a GNU sed extension) lead to arbitrary code execution. + +xzgrep from XZ Utils versions up to and including 5.2.5 are +affected. 5.3.1alpha and 5.3.2alpha are affected as well. +This patch works for all of them. + +This bug was inherited from gzip's zgrep. gzip 1.12 includes +a fix for zgrep. + +The issue with the old sed script is that with multiple newlines, +the N-command will read the second line of input, then the +s-commands will be skipped because it's not the end of the +file yet, then a new sed cycle starts and the pattern space +is printed and emptied. So only the last line or two get escaped. + +One way to fix this would be to read all lines into the pattern +space first. However, the included fix is even simpler: All lines +except the last line get a backslash appended at the end. To ensure +that shell command substitution doesn't eat a possible trailing +newline, a colon is appended to the filename before escaping. +The colon is later used to separate the filename from the grep +output so it is fine to add it here instead of a few lines later. + +The old code also wasn't POSIX compliant as it used \n in the +replacement section of the s-command. Using \ is the +POSIX compatible method. + +LC_ALL=C was added to the two critical sed commands. POSIX sed +manual recommends it when using sed to manipulate pathnames +because in other locales invalid multibyte sequences might +cause issues with some sed implementations. In case of GNU sed, +these particular sed scripts wouldn't have such problems but some +other scripts could have, see: + + info '(sed)Locale Considerations' + +This vulnerability was discovered by: +cleemy desu wayo working with Trend Micro Zero Day Initiative + +Thanks to Jim Meyering and Paul Eggert discussing the different +ways to fix this and for coordinating the patch release schedule +with gzip. +--- + src/scripts/xzgrep.in | 20 ++++++++++++-------- + 1 file changed, 12 insertions(+), 8 deletions(-) + +diff --git a/src/scripts/xzgrep.in b/src/scripts/xzgrep.in +index b180936..e5186ba 100644 +--- a/src/scripts/xzgrep.in ++++ b/src/scripts/xzgrep.in +@@ -180,22 +180,26 @@ for i; do + { test $# -eq 1 || test $no_filename -eq 1; }; then + eval "$grep" + else ++ # Append a colon so that the last character will never be a newline ++ # which would otherwise get lost in shell command substitution. ++ i="$i:" ++ ++ # Escape & \ | and newlines only if such characters are present ++ # (speed optimization). + case $i in + (*' + '* | *'&'* | *'\'* | *'|'*) +- i=$(printf '%s\n' "$i" | +- sed ' +- $!N +- $s/[&\|]/\\&/g +- $s/\n/\\n/g +- ');; ++ i=$(printf '%s\n' "$i" | LC_ALL=C sed 's/[&\|]/\\&/g; $!s/$/\\/');; + esac +- sed_script="s|^|$i:|" ++ ++ # $i already ends with a colon so don't add it here. ++ sed_script="s|^|$i|" + + # Fail if grep or sed fails. + r=$( + exec 4>&1 +- (eval "$grep" 4>&-; echo $? >&4) 3>&- | sed "$sed_script" >&3 4>&- ++ (eval "$grep" 4>&-; echo $? >&4) 3>&- | ++ LC_ALL=C sed "$sed_script" >&3 4>&- + ) || r=2 + exit $r + fi >&3 5>&- +-- +2.35.1 +