diff --git a/meta-python/recipes-devtools/python/python3-zeroconf/CVE-2026-47180.patch b/meta-python/recipes-devtools/python/python3-zeroconf/CVE-2026-47180.patch new file mode 100644 index 0000000000..7d27066d6f --- /dev/null +++ b/meta-python/recipes-devtools/python/python3-zeroconf/CVE-2026-47180.patch @@ -0,0 +1,110 @@ +From 7ffd3a90230cb99bcae4350fcb8498c48044f6a6 Mon Sep 17 00:00:00 2001 +From: "J. Nick Koston" +Date: Sun, 17 May 2026 19:48:44 -0700 +Subject: [PATCH] fix: bound DNS compression-pointer chain depth in DNSIncoming + (#1719) + +(cherry picked from commit f9e23592137f30fdf7ef710dba065da31c79b1cf) + +CVE: CVE-2026-47180 +Upstream-Status: Backport [https://github.com/python-zeroconf/python-zeroconf/commit/f9e23592137f30fdf7ef710dba065da31c79b1cf] +Signed-off-by: Ankur Tyagi +--- + src/zeroconf/_protocol/incoming.pxd | 2 +- + src/zeroconf/_protocol/incoming.py | 14 ++++++++++---- + tests/test_protocol.py | 22 ++++++++++++++++++++++ + 3 files changed, 33 insertions(+), 5 deletions(-) + +diff --git a/src/zeroconf/_protocol/incoming.pxd b/src/zeroconf/_protocol/incoming.pxd +index feaa2a0..eface8d 100644 +--- a/src/zeroconf/_protocol/incoming.pxd ++++ b/src/zeroconf/_protocol/incoming.pxd +@@ -83,7 +83,7 @@ cdef class DNSIncoming: + link_py_int=object, + linked_labels=cython.list + ) +- cdef unsigned int _decode_labels_at_offset(self, unsigned int off, cython.list labels, cython.set seen_pointers) ++ cdef unsigned int _decode_labels_at_offset(self, unsigned int off, cython.list labels, cython.set seen_pointers, unsigned int depth) + + @cython.locals(offset="unsigned int") + cdef void _read_header(self) +diff --git a/src/zeroconf/_protocol/incoming.py b/src/zeroconf/_protocol/incoming.py +index 2d977b6..d772f47 100644 +--- a/src/zeroconf/_protocol/incoming.py ++++ b/src/zeroconf/_protocol/incoming.py +@@ -60,7 +60,7 @@ DNS_COMPRESSION_POINTER_LEN = 2 + MAX_DNS_LABELS = 128 + MAX_NAME_LENGTH = 253 + +-DECODE_EXCEPTIONS = (IndexError, struct.error, IncomingDecodeError) ++DECODE_EXCEPTIONS = (IndexError, struct.error, IncomingDecodeError, RecursionError) + + + _seen_logs: dict[str, int | tuple] = {} +@@ -409,7 +409,7 @@ class DNSIncoming: + labels: list[str] = [] + seen_pointers: set[int] = set() + original_offset = self.offset +- self.offset = self._decode_labels_at_offset(original_offset, labels, seen_pointers) ++ self.offset = self._decode_labels_at_offset(original_offset, labels, seen_pointers, 0) + self._name_cache[original_offset] = labels + name = ".".join(labels) + "." + if len(name) > MAX_NAME_LENGTH: +@@ -418,8 +418,14 @@ class DNSIncoming: + ) + return name + +- def _decode_labels_at_offset(self, off: _int, labels: list[str], seen_pointers: set[int]) -> int: ++ def _decode_labels_at_offset( ++ self, off: _int, labels: list[str], seen_pointers: set[int], depth: _int ++ ) -> int: + # This is a tight loop that is called frequently, small optimizations can make a difference. ++ if depth > MAX_DNS_LABELS: ++ raise IncomingDecodeError( ++ f"DNS compression pointer chain exceeds {MAX_DNS_LABELS} at {off} from {self.source}" ++ ) + view = self.view + while off < self._data_len: + length = view[off] +@@ -457,7 +463,7 @@ class DNSIncoming: + if not linked_labels: + linked_labels = [] + seen_pointers.add(link_py_int) +- self._decode_labels_at_offset(link, linked_labels, seen_pointers) ++ self._decode_labels_at_offset(link, linked_labels, seen_pointers, depth + 1) + self._name_cache[link_py_int] = linked_labels + labels.extend(linked_labels) + if len(labels) > MAX_DNS_LABELS: +diff --git a/tests/test_protocol.py b/tests/test_protocol.py +index edd87c2..bac2b44 100644 +--- a/tests/test_protocol.py ++++ b/tests/test_protocol.py +@@ -1011,6 +1011,28 @@ def test_label_compression_attack(): + assert len(parsed.answers()) == 1 + + ++def test_dns_compression_pointer_chain_depth_attack() -> None: ++ """Test our wire parser rejects deeply chained compression pointers without recursing.""" ++ # Build a packet with one question whose name is a 1500-deep chain of forward ++ # compression pointers, ending in a root label. Each pointer is 2 bytes, ++ # so chain length easily exceeds CPython's default recursion limit. ++ header = b"\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00" ++ # Question at offset 12: pointer to offset 18 (past the question's type/class). ++ question_name = bytes([0xC0, 18]) ++ question_type_class = b"\x00\x01\x00\x01" ++ chain_depth = 1500 ++ chain = bytearray() ++ for i in range(chain_depth): ++ target = 18 + 2 * (i + 1) ++ chain.append(0xC0 | (target >> 8)) ++ chain.append(target & 0xFF) ++ chain.append(0x00) ++ packet = header + question_name + question_type_class + bytes(chain) ++ parsed = r.DNSIncoming(packet, ("1.2.3.4", 5353)) ++ assert parsed.valid is False ++ assert parsed.questions == [] ++ ++ + def test_dns_compression_loop_attack(): + """Test our wire parser does not loop forever when dns compression is in a loop.""" + packet = ( diff --git a/meta-python/recipes-devtools/python/python3-zeroconf_0.148.0.bb b/meta-python/recipes-devtools/python/python3-zeroconf_0.148.0.bb index fd083d6ee8..c405e83b8c 100644 --- a/meta-python/recipes-devtools/python/python3-zeroconf_0.148.0.bb +++ b/meta-python/recipes-devtools/python/python3-zeroconf_0.148.0.bb @@ -5,6 +5,8 @@ LIC_FILES_CHKSUM = "file://COPYING;md5=9fe712b1bc27c5c4e9ecd7f31d208900" SRC_URI[sha256sum] = "03fcca123df3652e23d945112d683d2f605f313637611b7d4adf31056f681702" +SRC_URI += "file://CVE-2026-47180.patch" + inherit pypi python_poetry_core cython RDEPENDS:${PN} += " \