Arista Eos 4.17

On affected platforms running Arista EOS, an authorized attacker with permissions to perform gNMI requests could craft a request allowing it to update arbitrary configurations in the switch. This situation occurs only when the Streaming Telemetry Agent (referred to as the TerminAttr agent) is enabled and gNMI access is configured on the agent. Note: This gNMI over the Streaming Telemetry Agent scenario is mostly commonly used when streaming to a 3rd party system and is not used by default when streaming to CloudVision

On affected modular platforms running Arista EOS equipped with both redundant supervisor modules and having the redundancy protocol configured with RPR or SSO, an existing unprivileged user can login to the standby supervisor as a root user, leading to a privilege escalation. Valid user credentials are required in order to exploit this vulnerability.

On affected platforms running Arista EOS with SNMP configured, a specially crafted packet can cause a memory leak in the snmpd process. This may result in the snmpd processing being terminated (causing SNMP requests to time out until snmpd is automatically restarted) and potential memory resource exhaustion for other processes on the switch. The vulnerability does not have any confidentiality or integrity impacts to the system.

For certain systems running EOS, a Precision Time Protocol (PTP) packet of a management/signaling message with an invalid Type-Length-Value (TLV) causes the PTP agent to restart. Repeated restarts of the service will make the service unavailable.

This advisory documents the impact of an internally found vulnerability in Arista EOS for security ACL bypass. The impact of this vulnerability is that the security ACL drop rule might be bypassed if a NAT ACL rule filter with permit action matches the packet flow. This could allow a host with an IP address in a range that matches the range allowed by a NAT ACL and a range denied by a Security ACL to be forwarded incorrectly as it should have been denied by the Security ACL. This can enable an ACL bypass.

This advisory documents the impact of an internally found vulnerability in Arista EOS state streaming telemetry agent TerminAttr and OpenConfig transport protocols. The impact of this vulnerability is that, in certain conditions, TerminAttr might leak MACsec sensitive data in clear text in CVP to other authorized users, which could cause MACsec traffic to be decrypted or modified by other authorized users on the device.

This advisory documents the impact of an internally found vulnerability in Arista EOS state streaming telemetry agent TerminAttr and OpenConfig transport protocols. The impact of this vulnerability is that, in certain conditions, TerminAttr might leak IPsec sensitive data in clear text in CVP to other authorized users, which could cause IPsec traffic to be decrypted or modified by other authorized users on the device.

On affected Arista EOS platforms, if a VXLAN match rule exists in an IPv4 access-list that is applied to the ingress of an L2 or an L3 port/SVI, the VXLAN rule and subsequent ACL rules in that access list will ignore the specified IP protocol.

On Arista Strata family products which have “TCAM profile†feature enabled when Port IPv4 access-list has a rule which matches on “vxlan†as protocol then that rule and subsequent rules ( rules declared after it in ACL ) do not match on IP protocol field as expected.

The impact of this vulnerability is that Arista's EOS eAPI may skip re-evaluating user credentials when certificate based authentication is used, which allows remote attackers to access the device via eAPI.

An issue has recently been discovered in Arista EOS where, under certain conditions, the service ACL configured for OpenConfig gNOI and OpenConfig RESTCONF might be bypassed, which results in the denied requests being forwarded to the agent.

An issue has recently been discovered in Arista EOS where certain gNOI APIs incorrectly skip authorization and authentication which could potentially allow a factory reset of the device.

An issue has recently been discovered in Arista EOS where the incorrect use of EOS's AAA API’s by the OpenConfig and TerminAttr agents could result in unrestricted access to the device for local users with nopassword configuration.

On systems running Arista EOS and CloudEOS with the affected release version, when using shared secret profiles the password configured for use by BiDirectional Forwarding Detection (BFD) will be leaked when displaying output over eAPI or other JSON outputs to other authenticated users on the device. The affected EOS Versions are: all releases in 4.22.x train, 4.23.9 and below releases in the 4.23.x train, 4.24.7 and below releases in the 4.24.x train, 4.25.4 and below releases in the 4.25.x train, 4.26.1 and below releases in the 4.26.x train

A flaw was found in dnsmasq before version 2.83. When receiving a query, dnsmasq does not check for an existing pending request for the same name and forwards a new request. By default, a maximum of 150 pending queries can be sent to upstream servers, so there can be at most 150 queries for the same name. This flaw allows an off-path attacker on the network to substantially reduce the number of attempts that it would have to perform to forge a reply and have it accepted by dnsmasq. This issue is mentioned in the "Birthday Attacks" section of RFC5452. If chained with CVE-2020-25684, the attack complexity of a successful attack is reduced. The highest threat from this vulnerability is to data integrity.

A flaw was found in dnsmasq before version 2.83. When getting a reply from a forwarded query, dnsmasq checks in forward.c:reply_query(), which is the forwarded query that matches the reply, by only using a weak hash of the query name. Due to the weak hash (CRC32 when dnsmasq is compiled without DNSSEC, SHA-1 when it is) this flaw allows an off-path attacker to find several different domains all having the same hash, substantially reducing the number of attempts they would have to perform to forge a reply and get it accepted by dnsmasq. This is in contrast with RFC5452, which specifies that the query name is one of the attributes of a query that must be used to match a reply. This flaw could be abused to perform a DNS Cache Poisoning attack. If chained with CVE-2020-25684 the attack complexity of a successful attack is reduced. The highest threat from this vulnerability is to data integrity.

A flaw was found in dnsmasq before version 2.83. When getting a reply from a forwarded query, dnsmasq checks in the forward.c:reply_query() if the reply destination address/port is used by the pending forwarded queries. However, it does not use the address/port to retrieve the exact forwarded query, substantially reducing the number of attempts an attacker on the network would have to perform to forge a reply and get it accepted by dnsmasq. This issue contrasts with RFC5452, which specifies a query's attributes that all must be used to match a reply. This flaw allows an attacker to perform a DNS Cache Poisoning attack. If chained with CVE-2020-25685 or CVE-2020-25686, the attack complexity of a successful attack is reduced. The highest threat from this vulnerability is to data integrity.

In EVPN VxLAN setups in Arista EOS, specific malformed packets can lead to incorrect MAC to IP bindings and as a result packets can be incorrectly forwarded across VLAN boundaries. This can result in traffic being discarded on the receiving VLAN. This affects versions: 4.21.12M and below releases in the 4.21.x train; 4.22.7M and below releases in the 4.22.x train; 4.23.5M and below releases in the 4.23.x train; 4.24.2F and below releases in the 4.24.x train.

An issue with ARP packets in Arista’s EOS affecting the 7800R3, 7500R3, and 7280R3 series of products may result in issues that cause a kernel crash, followed by a device reload. The affected Arista EOS versions are: 4.24.2.4F and below releases in the 4.24.x train; 4.23.4M and below releases in the 4.23.x train; 4.22.6M and below releases in the 4.22.x train.

In Arista EOS malformed packets can be incorrectly forwarded across VLAN boundaries in one direction. This vulnerability is only susceptible to exploitation by unidirectional traffic (ex. UDP) and not bidirectional traffic (ex. TCP). This affects: EOS 7170 platforms version 4.21.4.1F and below releases in the 4.21.x train; EOS X-Series versions 4.21.11M and below releases in the 4.21.x train; 4.22.6M and below releases in the 4.22.x train; 4.23.4M and below releases in the 4.23.x train; 4.24.2.1F and below releases in the 4.24.x train.

Arista EOS before 4.21.12M, 4.22.x before 4.22.7M, 4.23.x before 4.23.5M, and 4.24.x before 4.24.2F allows remote attackers to cause traffic loss or incorrect forwarding of traffic via a malformed link-state PDU to the IS-IS router.

Arista EOS before 4.21.12M, 4.22.x before 4.22.7M, 4.23.x before 4.23.5M, and 4.24.x before 4.24.2F allows remote attackers to cause a denial of service (restart of agents) by crafting a malformed DHCP packet which leads to an incorrect route being installed.

An issue was found in Arista EOS. Specific malformed ARP packets can impact the software forwarding of VxLAN packets. This issue is found in Arista’s EOS VxLAN code, which can allow attackers to crash the VxlanSwFwd agent. This affects EOS 4.21.8M and below releases in the 4.21.x train, 4.22.3M and below releases in the 4.22.x train, 4.23.1F and below releases in the 4.23.x train, and all releases in 4.15, 4.16, 4.17, 4.18, 4.19, 4.20 code train.

utility.c in telnetd in netkit telnet through 0.17 allows remote attackers to execute arbitrary code via short writes or urgent data, because of a buffer overflow involving the netclear and nextitem functions.

Go before 1.12.11 and 1.3.x before 1.13.2 can panic upon an attempt to process network traffic containing an invalid DSA public key. There are several attack scenarios, such as traffic from a client to a server that verifies client certificates.