A Use of Uninitialized Resource vulnerability in the Border Gateway Protocol (BGP) software of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated network-based attacker to send specific genuine BGP packets to a device configured with BGP to cause a Denial of Service (DoS) by crashing the Routing Protocol Daemon (rpd). This issue is triggered when the packets attempt to initiate a BGP connection before a BGP session is successfully established. Continued receipt of these specific BGP packets will cause a sustained Denial of Service condition. This issue is triggerable in both iBGP and eBGP deployments. This issue affects: Juniper Networks Junos OS 21.1 version 21.1R1 and later versions prior to 21.1R3-S5; 21.2 version 21.2R1 and later versions prior to 21.2R3-S2; 21.3 version 21.3R1 and later versions prior to 21.3R3-S2; 21.4 versions prior to 21.4R3; 22.1 versions prior to 22.1R3; 22.2 versions prior to 22.2R2. This issue does not affect Juniper Networks Junos OS versions prior to 21.1R1. This issue affects: Juniper Networks Junos OS Evolved 21.1-EVO version 21.1R1-EVO and later versions prior to 21.4R3-EVO; 22.1-EVO versions prior to 22.1R3-EVO; 22.2-EVO versions prior to 22.2R2-EVO. This issue does not affect Juniper Networks Junos OS Evolved versions prior to 21.1R1-EVO.

A vulnerability in the implementation of the Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. This vulnerability is due to the incorrect processing of a BGP update message that contains specific EVPN attributes. An attacker could exploit this vulnerability by sending a BGP update message that contains specific EVPN attributes. To exploit this vulnerability, an attacker must control a BGP speaker that has an established trusted peer connection to an affected device that is configured with the address family L2VPN EVPN to receive and process the update message. This vulnerability cannot be exploited by any data that is initiated by clients on the Layer 2 network or by peers that are not configured to accept the L2VPN EVPN address family. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP updates only from explicitly defined peers. For this vulnerability to be exploited, the malicious BGP update message must either come from a configured, valid BGP peer or be injected by the attacker into the affected BGP network on an existing, valid TCP connection to a BGP peer.

A vulnerability in the implementation of the Resource Public Key Infrastructure (RPKI) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the Border Gateway Protocol (BGP) process to crash, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of a specific RPKI to Router (RTR) Protocol packet header. An attacker could exploit this vulnerability by compromising the RPKI validator server and sending a specifically crafted RTR packet to an affected device. Alternatively, the attacker could use man-in-the-middle techniques to impersonate the RPKI validator server and send a crafted RTR response packet over the established RTR TCP connection to the affected device. A successful exploit could allow the attacker to cause a DoS condition because the BGP process could constantly restart and BGP routing could become unstable.

A vulnerability with the Border Gateway Protocol (BGP) for Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, remote attacker to cause a routing process to crash, which could lead to a denial of service (DoS) condition. This vulnerability is due to an issue with the installation of routes upon receipt of a BGP update. An attacker could exploit this vulnerability by sending a crafted BGP update to an affected device. A successful exploit could allow the attacker to cause the routing process to crash, which could cause the device to reload. This vulnerability applies to both Internal BGP (IBGP) and External BGP (EBGP). Note: The Cisco implementation of BGP accepts incoming BGP traffic from explicitly configured peers only. To exploit this vulnerability, an attacker would need to send a specific BGP update message over an established TCP connection that appears to come from a trusted BGP peer.

A vulnerability in the implementation of Multiprotocol Border Gateway Protocol (MP-BGP) for the Layer 2 VPN (L2VPN) Ethernet VPN (EVPN) address family in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of Border Gateway Protocol (BGP) update messages that contain crafted EVPN attributes. An attacker could exploit this vulnerability by sending BGP update messages with specific, malformed attributes to an affected device. A successful exploit could allow the attacker to cause an affected device to crash, resulting in a DoS condition.

Multiple vulnerabilities in the implementation of Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerabilities are due to incorrect processing of BGP update messages that contain crafted EVPN attributes. An attacker could exploit these vulnerabilities by sending BGP EVPN update messages with malformed attributes to be processed by an affected system. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic only from explicitly defined peers. To exploit these vulnerabilities, the malicious BGP update message would need to come from a configured, valid BGP peer, or would need to be injected by the attacker into the victim's BGP network on an existing, valid TCP connection to a BGP peer.

Multiple vulnerabilities in the implementation of Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerabilities are due to incorrect processing of BGP update messages that contain crafted EVPN attributes. An attacker could exploit these vulnerabilities by sending BGP EVPN update messages with malformed attributes to be processed by an affected system. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic only from explicitly defined peers. To exploit these vulnerabilities, the malicious BGP update message would need to come from a configured, valid BGP peer, or would need to be injected by the attacker into the victim's BGP network on an existing, valid TCP connection to a BGP peer.

Multiple vulnerabilities in the implementation of Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerabilities are due to incorrect processing of BGP update messages that contain crafted EVPN attributes. An attacker could exploit these vulnerabilities by sending BGP EVPN update messages with malformed attributes to be processed by an affected system. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic only from explicitly defined peers. To exploit these vulnerabilities, the malicious BGP update message would need to come from a configured, valid BGP peer, or would need to be injected by the attacker into the victim's BGP network on an existing, valid TCP connection to a BGP peer.

A vulnerability in the Border Gateway Protocol (BGP) Multicast VPN (MVPN) implementation of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a BGP session to repeatedly reset, causing a partial denial of service (DoS) condition due to the BGP session being down. The vulnerability is due to incorrect parsing of a specific type of BGP MVPN update message. An attacker could exploit this vulnerability by sending this BGP MVPN update message to a targeted device. A successful exploit could allow the attacker to cause the BGP peer connections to reset, which could lead to BGP route instability and impact traffic. The incoming BGP MVPN update message is valid but is parsed incorrectly by the NX-OS device, which could send a corrupted BGP update to the configured BGP peer. Note: The Cisco implementation of BGP accepts incoming BGP traffic from only explicitly configured peers. To exploit this vulnerability, an attacker must send a specific BGP MVPN update message over an established TCP connection that appears to come from a trusted BGP peer. To do so, the attacker must obtain information about the BGP peers in the trusted network of the affected system.

A vulnerability in the Border Gateway Protocol (BGP) Multicast VPN (MVPN) implementation of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause an affected device to unexpectedly reload, resulting in a denial of service (DoS) condition. The vulnerability is due to incomplete input validation of a specific type of BGP MVPN update message. An attacker could exploit this vulnerability by sending this specific, valid BGP MVPN update message to a targeted device. A successful exploit could allow the attacker to cause one of the BGP-related routing applications to restart multiple times, leading to a system-level restart. Note: The Cisco implementation of BGP accepts incoming BGP traffic from only explicitly configured peers. To exploit this vulnerability, an attacker must send a specific BGP MVPN update message over an established TCP connection that appears to come from a trusted BGP peer. To do so, the attacker must obtain information about the BGP peers in the trusted network of the affected system.

A vulnerability in the Border Gateway Protocol (BGP) additional paths feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to prevent authorized users from monitoring the BGP status and cause the BGP process to stop processing new updates, resulting in a denial of service (DOS) condition. The vulnerability is due to an incorrect calculation of lexicographical order when displaying additional path information within Cisco IOS XR Software, which causes an infinite loop. An attacker could exploit this vulnerability by sending a specific BGP update from a BGP neighbor peer session of an affected device; an authorized user must then issue a show bgp command for the vulnerability to be exploited. A successful exploit could allow the attacker to prevent authorized users from properly monitoring the BGP status and prevent BGP from processing new updates, resulting in outdated information in the routing and forwarding tables.

A vulnerability in the implementation of the Border Gateway Protocol (BGP) module in Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of certain BGP packets. An attacker could exploit this vulnerability by sending a crafted BGP packet. A successful exploit could allow the attacker to cause a DoS condition on the affected device.

A vulnerability in the implementation of Border Gateway Protocol (BGP) Message Digest 5 (MD5) authentication in Cisco NX-OS Software could allow an unauthenticated, remote attacker to bypass MD5 authentication and establish a BGP connection with the device. The vulnerability occurs because the BGP MD5 authentication is bypassed if the peer does not have MD5 authentication configured, the NX-OS device does have BGP MD5 authentication configured, and the NX-OS BGP virtual routing and forwarding (VRF) name is configured to be greater than 19 characters. An attacker could exploit this vulnerability by attempting to establish a BGP session with the NX-OS peer. A successful exploit could allow the attacker to establish a BGP session with the NX-OS device without MD5 authentication. The Cisco implementation of the BGP protocol accepts incoming BGP traffic only from explicitly configured peers. To exploit this vulnerability, an attacker must send the malicious packets over a TCP connection that appears to come from a trusted BGP peer. To do so, the attacker must obtain information about the BGP peers in the affected system’s trusted network.

Multiple vulnerabilities in the implementation of Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerabilities are due to incorrect processing of BGP update messages that contain crafted EVPN attributes. An attacker could exploit these vulnerabilities by sending BGP EVPN update messages with malformed attributes to be processed by an affected system. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic only from explicitly defined peers. To exploit these vulnerabilities, the malicious BGP update message would need to come from a configured, valid BGP peer, or would need to be injected by the attacker into the victim's BGP network on an existing, valid TCP connection to a BGP peer.

Multiple vulnerabilities in the implementation of Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerabilities are due to incorrect processing of BGP update messages that contain crafted EVPN attributes. An attacker could exploit these vulnerabilities by sending BGP EVPN update messages with malformed attributes to be processed by an affected system. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic only from explicitly defined peers. To exploit these vulnerabilities, the malicious BGP update message would need to come from a configured, valid BGP peer, or would need to be injected by the attacker into the victim's BGP network on an existing, valid TCP connection to a BGP peer.

A vulnerability in the implementation of Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of a BGP update message that contains crafted EVPN attributes. An attacker could indirectly exploit the vulnerability by sending BGP EVPN update messages with a specific, malformed attribute to an affected system and waiting for a user on the device to display the EVPN operational routes’ status. If successful, the attacker could cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic only from explicitly defined peers. To exploit this vulnerability, the malicious BGP update message would need to come from a configured, valid BGP peer, or would need to be injected by the attacker into the victim's BGP network on an existing, valid TCP connection to a BGP peer.

A vulnerability in the implementation of the Border Gateway Protocol (BGP) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of a BGP update message that contains a specific BGP attribute. An attacker could exploit this vulnerability by sending BGP update messages that include a specific, malformed attribute to be processed by an affected system. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic only from explicitly defined peers. To exploit this vulnerability, the malicious BGP update message would need to come from a configured, valid BGP peer or would need to be injected by the attacker into the victim’s BGP network on an existing, valid TCP connection to a BGP peer.

A vulnerability in the implementation of Border Gateway Protocol (BGP) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected system. The vulnerability is due to incorrect processing of certain BGP update messages. An attacker could exploit this vulnerability by sending BGP update messages that include a specific set of attributes to be processed by an affected system. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic from explicitly defined peers only. To exploit this vulnerability, the malicious BGP update message would need to come from a configured, valid BGP peer or would need to be injected by the attacker into the victim's BGP network on an existing, valid TCP connection to a BGP peer.

A vulnerability in the implementation of Border Gateway Protocol (BGP) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of certain BGP update messages. An attacker could exploit this vulnerability by sending BGP update messages that include a specific, malformed attribute to be processed by an affected system. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic only from explicitly defined peers. To exploit this vulnerability, the malicious BGP update message would need to come from a configured, valid BGP peer, or would need to be injected by the attacker into the victim's BGP network on an existing, valid TCP connection to a BGP peer.

A vulnerability in the Border Gateway Protocol (BGP) implementation of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition due to the device unexpectedly reloading. The vulnerability is due to incomplete input validation of the BGP update messages. An attacker could exploit this vulnerability by sending a crafted BGP update message to the targeted device. An exploit could allow the attacker to cause the switch to reload unexpectedly. The Cisco implementation of the BGP protocol only accepts incoming BGP traffic from explicitly defined peers. To exploit this vulnerability, an attacker must be able to send the malicious packets over a TCP connection that appears to come from a trusted BGP peer or inject malformed messages into the victim's BGP network. This would require obtaining information about the BGP peers in the affected system's trusted network. The vulnerability may be triggered when the router receives a malformed BGP message from a peer on an existing BGP session. At least one BGP neighbor session must be established for a router to be vulnerable. This vulnerability affects Nexus 2000 Series Switches, Nexus 3000 Series Switches, Nexus 3500 Platform Switches, Nexus 3600 Platform Switches, Nexus 5500 Platform Switches, Nexus 5600 Platform Switches, Nexus 6000 Series Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches, Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode, Nexus 9000 Series Switches in standalone NX-OS mode, Nexus 9500 R-Series Line Cards and Fabric Modules. Cisco Bug IDs: CSCve79599, CSCve87784, CSCve91371, CSCve91387.