Security fix for CVE-2015-20107

Resolves: rhbz#2075390

00382-cve-2015-20107.patch

@@ -0,0 +1,150 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Petr Viktorin <encukou@gmail.com>
+Date: Fri, 3 Jun 2022 11:43:35 +0200
+Subject: [PATCH] 00382: CVE-2015-20107
+
+Make mailcap refuse to match unsafe filenames/types/params (GH-91993)
+
+Upstream: https://github.com/python/cpython/issues/68966
+
+Tracker bug: https://bugzilla.redhat.com/show_bug.cgi?id=2075390
+---
+ Doc/library/mailcap.rst                       | 12 +++++++++
+ Lib/mailcap.py                                | 26 +++++++++++++++++--
+ Lib/test/test_mailcap.py                      |  8 ++++--
+ ...2-04-27-18-25-30.gh-issue-68966.gjS8zs.rst |  4 +++
+ 4 files changed, 46 insertions(+), 4 deletions(-)
+ create mode 100644 Misc/NEWS.d/next/Security/2022-04-27-18-25-30.gh-issue-68966.gjS8zs.rst
+
+diff --git a/Doc/library/mailcap.rst b/Doc/library/mailcap.rst
+index a22b5b9c9e..7aa3380fec 100644
+--- a/Doc/library/mailcap.rst
++++ b/Doc/library/mailcap.rst
+@@ -60,6 +60,18 @@ standard.  However, mailcap files are supported on most Unix systems.
+    use) to determine whether or not the mailcap line applies.  :func:`findmatch`
+    will automatically check such conditions and skip the entry if the check fails.
+ 
++   .. versionchanged:: 3.11
++
++      To prevent security issues with shell metacharacters (symbols that have
++      special effects in a shell command line), ``findmatch`` will refuse
++      to inject ASCII characters other than alphanumerics and ``@+=:,./-_``
++      into the returned command line.
++
++      If a disallowed character appears in *filename*, ``findmatch`` will always
++      return ``(None, None)`` as if no entry was found.
++      If such a character appears elsewhere (a value in *plist* or in *MIMEtype*),
++      ``findmatch`` will ignore all mailcap entries which use that value.
++      A :mod:`warning <warnings>` will be raised in either case.
+ 
+ .. function:: getcaps()
+ 
+diff --git a/Lib/mailcap.py b/Lib/mailcap.py
+index ae416a8e9f..444c6408b5 100644
+--- a/Lib/mailcap.py
++++ b/Lib/mailcap.py
+@@ -2,6 +2,7 @@
+ 
+ import os
+ import warnings
++import re
+ 
+ __all__ = ["getcaps","findmatch"]
+ 
+@@ -13,6 +14,11 @@ def lineno_sort_key(entry):
+     else:
+         return 1, 0
+ 
++_find_unsafe = re.compile(r'[^\xa1-\U0010FFFF\w@+=:,./-]').search
++
++class UnsafeMailcapInput(Warning):
++    """Warning raised when refusing unsafe input"""
++
+ 
+ # Part 1: top-level interface.
+ 
+@@ -165,15 +171,22 @@ def findmatch(caps, MIMEtype, key='view', filename="/dev/null", plist=[]):
+     entry to use.
+ 
+     """
++    if _find_unsafe(filename):
++        msg = "Refusing to use mailcap with filename %r. Use a safe temporary filename." % (filename,)
++        warnings.warn(msg, UnsafeMailcapInput)
++        return None, None
+     entries = lookup(caps, MIMEtype, key)
+     # XXX This code should somehow check for the needsterminal flag.
+     for e in entries:
+         if 'test' in e:
+             test = subst(e['test'], filename, plist)
++            if test is None:
++                continue
+             if test and os.system(test) != 0:
+                 continue
+         command = subst(e[key], MIMEtype, filename, plist)
+-        return command, e
++        if command is not None:
++            return command, e
+     return None, None
+ 
+ def lookup(caps, MIMEtype, key=None):
+@@ -206,6 +219,10 @@ def subst(field, MIMEtype, filename, plist=[]):
+             elif c == 's':
+                 res = res + filename
+             elif c == 't':
++                if _find_unsafe(MIMEtype):
++                    msg = "Refusing to substitute MIME type %r into a shell command." % (MIMEtype,)
++                    warnings.warn(msg, UnsafeMailcapInput)
++                    return None
+                 res = res + MIMEtype
+             elif c == '{':
+                 start = i
+@@ -213,7 +230,12 @@ def subst(field, MIMEtype, filename, plist=[]):
+                     i = i+1
+                 name = field[start:i]
+                 i = i+1
+-                res = res + findparam(name, plist)
++                param = findparam(name, plist)
++                if _find_unsafe(param):
++                    msg = "Refusing to substitute parameter %r (%s) into a shell command" % (param, name)
++                    warnings.warn(msg, UnsafeMailcapInput)
++                    return None
++                res = res + param
+             # XXX To do:
+             # %n == number of parts if type is multipart/*
+             # %F == list of alternating type and filename for parts
+diff --git a/Lib/test/test_mailcap.py b/Lib/test/test_mailcap.py
+index c08423c670..920283d9a2 100644
+--- a/Lib/test/test_mailcap.py
++++ b/Lib/test/test_mailcap.py
+@@ -121,7 +121,8 @@ class HelperFunctionTest(unittest.TestCase):
+             (["", "audio/*", "foo.txt"], ""),
+             (["echo foo", "audio/*", "foo.txt"], "echo foo"),
+             (["echo %s", "audio/*", "foo.txt"], "echo foo.txt"),
+-            (["echo %t", "audio/*", "foo.txt"], "echo audio/*"),
++            (["echo %t", "audio/*", "foo.txt"], None),
++            (["echo %t", "audio/wav", "foo.txt"], "echo audio/wav"),
+             (["echo \\%t", "audio/*", "foo.txt"], "echo %t"),
+             (["echo foo", "audio/*", "foo.txt", plist], "echo foo"),
+             (["echo %{total}", "audio/*", "foo.txt", plist], "echo 3")
+@@ -205,7 +206,10 @@ class FindmatchTest(unittest.TestCase):
+              ('"An audio fragment"', audio_basic_entry)),
+             ([c, "audio/*"],
+              {"filename": fname},
+-             ("/usr/local/bin/showaudio audio/*", audio_entry)),
++             (None, None)),
++            ([c, "audio/wav"],
++             {"filename": fname},
++             ("/usr/local/bin/showaudio audio/wav", audio_entry)),
+             ([c, "message/external-body"],
+              {"plist": plist},
+              ("showexternal /dev/null default john python.org     /tmp foo bar", message_entry))
+diff --git a/Misc/NEWS.d/next/Security/2022-04-27-18-25-30.gh-issue-68966.gjS8zs.rst b/Misc/NEWS.d/next/Security/2022-04-27-18-25-30.gh-issue-68966.gjS8zs.rst
+new file mode 100644
+index 0000000000..da81a1f699
+--- /dev/null
++++ b/Misc/NEWS.d/next/Security/2022-04-27-18-25-30.gh-issue-68966.gjS8zs.rst
+@@ -0,0 +1,4 @@
++The deprecated mailcap module now refuses to inject unsafe text (filenames,
++MIME types, parameters) into shell commands. Instead of using such text, it
++will warn and act as if a match was not found (or for test commands, as if
++the test failed).

python3.9.spec

@@ -17,7 +17,7 @@ URL: https://www.python.org/
 #global prerel ...
 %global upstream_version %{general_version}%{?prerel}
 Version: %{general_version}%{?prerel:~%{prerel}}
-Release: 1%{?dist}
+Release: 2%{?dist}
 License: Python
 
 
@@ -399,6 +399,16 @@ Patch329: 00329-fips.patch
 # a nightmare because it's basically a binary file.
 Patch353: 00353-architecture-names-upstream-downstream.patch
 
+# 00382 # 9e275dcdf3934b827994ecc3247d583d5bab7985
+# CVE-2015-20107
+#
+# Make mailcap refuse to match unsafe filenames/types/params (GH-91993)
+#
+# Upstream: https://github.com/python/cpython/issues/68966
+#
+# Tracker bug: https://bugzilla.redhat.com/show_bug.cgi?id=2075390
+Patch382: 00382-cve-2015-20107.patch
+
 # (New patches go here ^^^)
 #
 # When adding new patches to "python" and "python3" in Fedora, EL, etc.,
@@ -1800,6 +1810,10 @@ CheckPython optimized
 # ======================================================
 
 %changelog
+* Thu Jun 09 2022 Charalampos Stratakis <cstratak@redhat.com> - 3.9.13-2
+- Security fix for CVE-2015-20107
+Resolves: rhbz#2075390
+
 * Wed Jun 01 2022 Charalampos Stratakis <cstratak@redhat.com> - 3.9.13-1
 - Update to 3.9.13
 Resolves: rhbz#2054702, rhbz#2059951