An issue was discovered in Open vSwitch (OvS) 2.7.x through 2.7.6, affecting ofproto_rule_insert__ in ofproto/ofproto.c. During bundle commit, flows that are added in a bundle are applied to ofproto in order. If a flow cannot be added (e.g., the flow action is a go-to for a group id that does not exist), OvS tries to revert back all previous flows that were successfully applied from the same bundle. This is possible since OvS maintains list of old flows that were replaced by flows from the bundle. While reinserting old flows, OvS has an assertion failure due to a check on rule state != RULE_INITIALIZED. This would work for new flows, but for an old flow the rule state is RULE_REMOVED. The assertion failure causes an OvS crash.

The remote Redhat Enterprise Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2019:0053 advisory.

    Open vSwitch provides standard network bridging functions and support for the OpenFlow protocol for remote     per-flow control of traffic.

    Security Fix(es):

    * openvswitch: Mishandle of group mods in lib/ofp-util.c:parse_group_prop_ntr_selection_method() allows     for assertion failure (CVE-2018-17204)

    * openvswitch: Error during bundle commit in ofproto/ofproto.c:ofproto_rule_insert__() allows for crash     (CVE-2018-17205)

    * openvswitch: Buffer over-read in lib/ofp-actions.c:decode_bundle() (CVE-2018-17206)

    For more details about the security issue(s), including the impact, a CVSS score, and other related     information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Redhat Enterprise Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2019:0081 advisory.

    Open vSwitch provides standard network bridging functions and support for the OpenFlow protocol for remote     per-flow control of traffic.

    Security Fix(es):

    * openvswitch: Mishandle of group mods in lib/ofp-util.c:parse_group_prop_ntr_selection_method() allows     for assertion failure (CVE-2018-17204)

    * openvswitch: Error during bundle commit in ofproto/ofproto.c:ofproto_rule_insert__() allows for crash     (CVE-2018-17205)

    * openvswitch: Buffer over-read in lib/ofp-actions.c:decode_bundle() (CVE-2018-17206)

    For more details about the security issue(s), including the impact, a CVSS score, and other related     information, refer to the CVE page(s) listed in the References section.

    Bug Fix(es):

    * Previously, the first packet of a new connection using an OVN logical router was used to discover the     MAC address of the destination. This resulted in the loss of the first packet on the new connection. This     enhancement adds the capability to correctly queue the first packet of a new connection, which prevents     the loss of that packet. (BZ#1600115)

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Ubuntu 16.04 LTS / 18.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-3873-1 advisory.

    It was discovered that Open vSwitch incorrectly decoded certain packets. A remote attacker could possibly     use this issue to cause Open vSwitch to crash, resulting in a denial of service. (CVE-2018-17204)

    It was discovered that Open vSwitch incorrectly handled processing certain flows. A remote attacker could     possibly use this issue to cause Open vSwitch to crash, resulting in a denial of service. This issue only     affected Ubuntu 18.04 LTS. (CVE-2018-17205)

    It was discovered that Open vSwitch incorrectly handled BUNDLE action decoding. A remote attacker could     possibly use this issue to cause Open vSwitch to crash, resulting in a denial of service. (CVE-2018-17206)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

This update for openvswitch to version 2.7.6 fixes the following issues :

These security issues were fixed :

CVE-2018-17205: Prevent OVS crash when reverting old flows in bundle commit (bsc#1104467).

CVE-2018-17206: Avoid buffer overread in BUNDLE action decoding (bsc#1104467).

CVE-2018-17204: When decoding a group mod, it validated the group type and command after the whole group mod has been decoded. The OF1.5 decoder, however, tried to use the type and command earlier, when it might still be invalid. This caused an assertion failure (via OVS_NOT_REACHED) (bsc#1104467).

The update package also includes non-security fixes. See advisory for details.

Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

This update for openvswitch to version 2.7.6 fixes the following issues :

These security issues were fixed :

  - CVE-2018-17205: Prevent OVS crash when reverting old     flows in bundle commit (bsc#1104467).

  - CVE-2018-17206: Avoid buffer overread in BUNDLE action     decoding (bsc#1104467).

  - CVE-2018-17204:When decoding a group mod, it validated     the group type and command after the whole group mod has     been decoded. The OF1.5 decoder, however, tried to use     the type and command earlier, when it might still be     invalid. This caused an assertion failure (via     OVS_NOT_REACHED) (bsc#1104467).

These non-security issues were fixed :

  - ofproto/bond: Fix bond reconfiguration race condition.

  - ofproto/bond: Fix bond post recirc rule leak.

  - ofproto/bond: fix interal flow leak of tcp-balance bond

  - systemd: Restart openvswitch service if a daemon crashes

  - conntrack: Fix checks for TCP, UDP, and IPv6 header     sizes.

  - ofp-actions: Fix translation of set_field for nw_ecn

  - netdev-dpdk: Fix mempool segfault.

  - ofproto-dpif-upcall: Fix flow setup/delete race.

  - learn: Fix memory leak in learn_parse_sepc()

  - netdev-dpdk: fix mempool_configure error state

  - vswitchd: Add --cleanup option to the 'appctl exit'     command

  - ofp-parse: Fix memory leak on error path in     parse_ofp_group_mod_file().

  - actions: Fix memory leak on error path in     parse_ct_lb_action().

  - dpif-netdev: Fix use-after-free error in     reconfigure_datapath().

  - bridge: Fix memory leak in bridge_aa_update_trunks().

  - dpif-netlink: Fix multiple-free and fd leak on error     path.

  - ofp-print: Avoid array overread in     print_table_instruction_features().

  - flow: Fix buffer overread in flow_hash_symmetric_l3l4().

  - systemd: start vswitchd after udev

  - ofp-util: Check length of buckets in     ofputil_pull_ofp15_group_mod().

  - ovsdb-types: Fix memory leak on error path.

  - tnl-ports: Fix loss of tunneling upon removal of a     single tunnel port.

  - netdev: check for NULL fields in netdev_get_addrs

  - netdev-dpdk: vhost get stats fix.

  - netdev-dpdk: use 64-bit arithmetic when converting     rates.

  - ofp-util: Fix buffer overread in     ofputil_decode_bundle_add().

  - ofp-util: Fix memory leaks on error cases in     ofputil_decode_group_mod().

  - ofp-util: Fix memory leaks when parsing OF1.5 group     properties.

  - ofp-actions: Fix buffer overread in     decode_LEARN_specs().

  - flow: Fix buffer overread for crafted IPv6 packets.

  - ofp-actions: Properly interpret 'output:in_port'.

  - ovs-ofctl: Avoid read overrun in ofperr_decode_msg().

  - odp-util: Avoid misaligned references to ip6_hdr.

  - ofproto-dpif-upcall: Fix action attr iteration.

  - ofproto-dpif-upcall: Fix key attr iteration.

  - netdev-dpdk: vhost get stats fix.

  - netdev-dpdk: use 64-bit arithmetic when converting     rates.

  - ofp-util: Fix buffer overread in     ofputil_decode_bundle_add().

  - ofp-util: Fix memory leaks on error cases in     ofputil_decode_group_mod().

  - ofp-util: Fix memory leaks when parsing OF1.5 group     properties.

  - odp-util: Fix buffer overread in parsing string form of     ODP flows.

  - ovs-vsctl: Fix segfault when attempting to del-port from     parent bridge.

This update was imported from the SUSE:SLE-12-SP3:Update update project.

The remote Redhat Enterprise Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2018:3500 advisory.

    Open vSwitch provides standard network bridging functions and support for the OpenFlow protocol for remote     per-flow control of traffic.

    Security Fix(es):

    * openvswitch: Mishandle of group mods in lib/ofp-util.c:parse_group_prop_ntr_selection_method() allows     for assertion failure (CVE-2018-17204)

    * openvswitch: Error during bundle commit in ofproto/ofproto.c:ofproto_rule_insert__() allows for crash     (CVE-2018-17205)

    * openvswitch: Buffer over-read in lib/ofp-actions.c:decode_bundle() (CVE-2018-17206)

    For more details about the security issue(s), including the impact, a CVSS score, and other related     information, refer to the CVE page(s) listed in the References section.

    Bug Fix(es):

    * Previously, when the ovs-vswitchd service restarted, an error displayed with many open files. With this     update, the number of sockets opened by ovs-vswitchd is decreased. As a result, the described problem no     longer occurs. (BZ#1526306)

    * Previously, when OpenvSwitch service was reloaded, the default flow was not removed and it became part     of the final flow table. With this update, the default flow rule is no longer added after a service     reload. As a result, the described problem no longer occurs. (BZ#1626096)

    Enhancement(s):

    * With this update, the pmd-rxq-assign configuration has been added to Poll Mode Drivers (PMDs) cores.
    This allows users to select a round-robin assignment. (BZ#1616001)

    * With this update the ovs-appctl connection-status command has been introduced to the ovs-appctl utility.
    The command enables to monitor hypervisor (HV) south bound database (SBDB) connection status. Layered     products can now check if the ovn-controller is properly connected to a central node. (BZ#1593804)

    * With this update, a support for the Dynamic Host Configuration Protocol (DHCP) option 252 has been added     to Open Virtual Network (OVN) Native DHCP. (BZ#1641765)

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
194036	RHEL 7 : openvswitch (RHSA-2019:0053)	Nessus	Red Hat Local Security Checks	high
194031	RHEL 7 : openvswitch (RHSA-2019:0081)	Nessus	Red Hat Local Security Checks	high
121506	Ubuntu 16.04 LTS / 18.04 LTS : Open vSwitch vulnerabilities (USN-3873-1)	Nessus	Ubuntu Local Security Checks	high
119720	SUSE SLES12 Security Update : openvswitch (SUSE-SU-2018:4128-1)	Nessus	SuSE Local Security Checks	high
119716	openSUSE Security Update : openvswitch (openSUSE-2018-1562)	Nessus	SuSE Local Security Checks	high
118745	RHEL 7 : openvswitch (RHSA-2018:3500)	Nessus	Red Hat Local Security Checks	high

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CVE-2018-17205

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