| From 532ed09c5454bb789a301bb6f1339a0818255610 Mon Sep 17 00:00:00 2001 |
| From: =?UTF-8?q?Roberto=20C=2E=20S=C3=A1nchez?= <roberto@connexer.com> |
| Date: Sat, 14 Sep 2019 13:26:38 -0400 |
| Subject: [PATCH] [2.7] bpo-34155: Dont parse domains containing @ (GH-13079) |
| (GH-16006) |
| |
| This change skips parsing of email addresses where domains include a "@" character, which can be maliciously used since the local part is returned as a complete address. |
| |
| (cherry picked from commit 8cb65d1381b027f0b09ee36bfed7f35bb4dec9a9) |
| |
| Excludes changes to Lib/email/_header_value_parser.py, which did not |
| exist in 2.7. |
| |
| Co-authored-by: jpic <jpic@users.noreply.github.com> |
| |
| https://bugs.python.org/issue34155 |
| |
| Upstream-Status: Backport [https://github.com/python/cpython/commit/8cb65d1381b027f0b09ee36bfed7f35bb4dec9a9] |
| |
| CVE: CVE-2019-16056 |
| |
| Signed-off-by: Chen Qi <Qi.Chen@windriver.com> |
| --- |
| Lib/email/_parseaddr.py | 11 ++++++++++- |
| Lib/email/test/test_email.py | 14 ++++++++++++++ |
| .../2019-05-04-13-33-37.bpo-34155.MJll68.rst | 1 + |
| 3 files changed, 25 insertions(+), 1 deletion(-) |
| create mode 100644 Misc/NEWS.d/next/Security/2019-05-04-13-33-37.bpo-34155.MJll68.rst |
| |
| diff --git a/Lib/email/_parseaddr.py b/Lib/email/_parseaddr.py |
| index 690db2c22d..dc49d2e45a 100644 |
| --- a/Lib/email/_parseaddr.py |
| +++ b/Lib/email/_parseaddr.py |
| @@ -336,7 +336,12 @@ class AddrlistClass: |
| aslist.append('@') |
| self.pos += 1 |
| self.gotonext() |
| - return EMPTYSTRING.join(aslist) + self.getdomain() |
| + domain = self.getdomain() |
| + if not domain: |
| + # Invalid domain, return an empty address instead of returning a |
| + # local part to denote failed parsing. |
| + return EMPTYSTRING |
| + return EMPTYSTRING.join(aslist) + domain |
| |
| def getdomain(self): |
| """Get the complete domain name from an address.""" |
| @@ -351,6 +356,10 @@ class AddrlistClass: |
| elif self.field[self.pos] == '.': |
| self.pos += 1 |
| sdlist.append('.') |
| + elif self.field[self.pos] == '@': |
| + # bpo-34155: Don't parse domains with two `@` like |
| + # `a@malicious.org@important.com`. |
| + return EMPTYSTRING |
| elif self.field[self.pos] in self.atomends: |
| break |
| else: |
| diff --git a/Lib/email/test/test_email.py b/Lib/email/test/test_email.py |
| index 4b4dee3d34..2efe44ac5a 100644 |
| --- a/Lib/email/test/test_email.py |
| +++ b/Lib/email/test/test_email.py |
| @@ -2306,6 +2306,20 @@ class TestMiscellaneous(TestEmailBase): |
| self.assertEqual(Utils.parseaddr('<>'), ('', '')) |
| self.assertEqual(Utils.formataddr(Utils.parseaddr('<>')), '') |
| |
| + def test_parseaddr_multiple_domains(self): |
| + self.assertEqual( |
| + Utils.parseaddr('a@b@c'), |
| + ('', '') |
| + ) |
| + self.assertEqual( |
| + Utils.parseaddr('a@b.c@c'), |
| + ('', '') |
| + ) |
| + self.assertEqual( |
| + Utils.parseaddr('a@172.17.0.1@c'), |
| + ('', '') |
| + ) |
| + |
| def test_noquote_dump(self): |
| self.assertEqual( |
| Utils.formataddr(('A Silly Person', 'person@dom.ain')), |
| diff --git a/Misc/NEWS.d/next/Security/2019-05-04-13-33-37.bpo-34155.MJll68.rst b/Misc/NEWS.d/next/Security/2019-05-04-13-33-37.bpo-34155.MJll68.rst |
| new file mode 100644 |
| index 0000000000..50292e29ed |
| --- /dev/null |
| +++ b/Misc/NEWS.d/next/Security/2019-05-04-13-33-37.bpo-34155.MJll68.rst |
| @@ -0,0 +1 @@ |
| +Fix parsing of invalid email addresses with more than one ``@`` (e.g. a@b@c.com.) to not return the part before 2nd ``@`` as valid email address. Patch by maxking & jpic. |