| Message ID | 20190312234651.13693-1-panfilov.artyom@gmail.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [v2] package/avahi: add upstream security fix | expand |
On Wed, 13 Mar 2019 02:46:51 +0300 Artem Panfilov <panfilov.artyom@gmail.com> wrote: > Fixes CVE-2017-6519: avahi-daemon in Avahi through 0.6.32 and 0.7 > inadvertently responds to IPv6 unicast queries with source addresses > that are not on-link, which allows remote attackers to cause a denial > of service (traffic amplification) and may cause information leakage > by obtaining potentially sensitive information from the responding > device via port-5353 UDP packets. > > Signed-off-by: Artem Panfilov <panfilov.artyom@gmail.com> > > --- > Changes v1 -> v2: > - add "Signed-off-by" and "Backported from" tags in patch > --- > ...ast-queries-from-address-not-on-loca.patch | 48 +++++++++++++++++++ > 1 file changed, 48 insertions(+) > create mode 100644 package/avahi/0001-Drop-legacy-unicast-queries-from-address-not-on-loca.patch Applied to master, thanks. Thomas
>>>>> "Artem" == Artem Panfilov <panfilov.artyom@gmail.com> writes: > Fixes CVE-2017-6519: avahi-daemon in Avahi through 0.6.32 and 0.7 > inadvertently responds to IPv6 unicast queries with source addresses > that are not on-link, which allows remote attackers to cause a denial > of service (traffic amplification) and may cause information leakage > by obtaining potentially sensitive information from the responding > device via port-5353 UDP packets. > Signed-off-by: Artem Panfilov <panfilov.artyom@gmail.com> > --- > Changes v1 -> v2: > - add "Signed-off-by" and "Backported from" tags in patch Committed to 2018.02.x, 2018.11.x and 2019.02.x, thanks.
diff --git a/package/avahi/0001-Drop-legacy-unicast-queries-from-address-not-on-loca.patch b/package/avahi/0001-Drop-legacy-unicast-queries-from-address-not-on-loca.patch new file mode 100644 index 0000000000..0e8408c830 --- /dev/null +++ b/package/avahi/0001-Drop-legacy-unicast-queries-from-address-not-on-loca.patch @@ -0,0 +1,48 @@ +From e111def44a7df4624a4aa3f85fe98054bffb6b4f Mon Sep 17 00:00:00 2001 +From: Trent Lloyd <trent@lloyd.id.au> +Date: Sat, 22 Dec 2018 09:06:07 +0800 +Subject: [PATCH] Drop legacy unicast queries from address not on local link + +When handling legacy unicast queries, ensure that the source IP is +inside a subnet on the local link, otherwise drop the packet. + +Fixes #145 +Fixes #203 +CVE-2017-6519 +CVE-2018-100084 + +Backported from: e111def44a7df4624a4aa3f85fe98054bffb6b4f +Signed-off-by: Artem Panfilov <panfilov.artyom@gmail.com> +--- + avahi-core/server.c | 8 ++++++++ + 1 file changed, 8 insertions(+) + +diff --git a/avahi-core/server.c b/avahi-core/server.c +index a2cb19a8..a2580e38 100644 +--- a/avahi-core/server.c ++++ b/avahi-core/server.c +@@ -930,6 +930,7 @@ static void dispatch_packet(AvahiServer *s, AvahiDnsPacket *p, const AvahiAddres + + if (avahi_dns_packet_is_query(p)) { + int legacy_unicast = 0; ++ char t[AVAHI_ADDRESS_STR_MAX]; + + /* For queries EDNS0 might allow ARCOUNT != 0. We ignore the + * AR section completely here, so far. Until the day we add +@@ -947,6 +948,13 @@ static void dispatch_packet(AvahiServer *s, AvahiDnsPacket *p, const AvahiAddres + legacy_unicast = 1; + } + ++ if (!is_mdns_mcast_address(dst_address) && ++ !avahi_interface_address_on_link(i, src_address)) { ++ ++ avahi_log_debug("Received non-local unicast query from host %s on interface '%s.%i'.", avahi_address_snprint(t, sizeof(t), src_address), i->hardware->name, i->protocol); ++ return; ++ } ++ + if (legacy_unicast) + reflect_legacy_unicast_query_packet(s, p, i, src_address, port); + +-- +2.19.1 +
Fixes CVE-2017-6519: avahi-daemon in Avahi through 0.6.32 and 0.7 inadvertently responds to IPv6 unicast queries with source addresses that are not on-link, which allows remote attackers to cause a denial of service (traffic amplification) and may cause information leakage by obtaining potentially sensitive information from the responding device via port-5353 UDP packets. Signed-off-by: Artem Panfilov <panfilov.artyom@gmail.com> --- Changes v1 -> v2: - add "Signed-off-by" and "Backported from" tags in patch --- ...ast-queries-from-address-not-on-loca.patch | 48 +++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 package/avahi/0001-Drop-legacy-unicast-queries-from-address-not-on-loca.patch