A vulnerability in the enhanced Preboot eXecution Environment (PXE) boot loader for Cisco IOS XR 64-bit Software could allow an unauthenticated, remote attacker to execute unsigned code during the PXE boot process on an affected device. The PXE boot loader is part of the BIOS and runs over the management interface of hardware platforms that are running Cisco IOS XR Software only. The vulnerability exists because internal commands that are issued when the PXE network boot process is loading a software image are not properly verified. An attacker could exploit this vulnerability by compromising the PXE boot server and replacing a valid software image with a malicious one. Alternatively, the attacker could impersonate the PXE boot server and send a PXE boot reply with a malicious file. A successful exploit could allow the attacker to execute unsigned code on the affected device. Note: To fix this vulnerability, both the Cisco IOS XR Software and the BIOS must be upgraded. The BIOS code is included in Cisco IOS XR Software but might require additional installation steps. For further information, see the Fixed Software section of this advisory.
CVSS Score
8.1
EPSS Score
0.038
Published
2020-11-06
CVE-2020-3569
Multiple vulnerabilities in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to either immediately crash the Internet Group Management Protocol (IGMP) process or make it consume available memory and eventually crash. The memory consumption may negatively impact other processes that are running on the device. These vulnerabilities are due to the incorrect handling of IGMP packets. An attacker could exploit these vulnerabilities by sending crafted IGMP traffic to an affected device. A successful exploit could allow the attacker to immediately crash the IGMP process or cause memory exhaustion, resulting in other processes becoming unstable. These processes may include, but are not limited to, interior and exterior routing protocols. Cisco will release software updates that address these vulnerabilities.
Known exploited
CVSS Score
8.6
EPSS Score
0.217
Published
2020-09-23
A vulnerability in task group assignment for a specific CLI command in Cisco IOS XR Software could allow an authenticated, local attacker to execute that command, even though administrative privileges should be required. The attacker must have valid credentials on the affected device. The vulnerability is due to incorrect mapping in the source code of task group assignments for a specific command. An attacker could exploit this vulnerability by issuing the command, which they should not be authorized to issue, on an affected device. A successful exploit could allow the attacker to invalidate the integrity of the disk and cause the device to restart. This vulnerability could allow a user with read permissions to issue a specific command that should require Administrator privileges.
CVSS Score
8.4
EPSS Score
0.0
Published
2020-09-04
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.
CVSS Score
4.3
EPSS Score
0.005
Published
2020-08-17
A vulnerability in the Topology Discovery Service of Cisco One Platform Kit (onePK) in Cisco IOS Software, Cisco IOS XE Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to execute arbitrary code or cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient length restrictions when the onePK Topology Discovery Service parses Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol message to an affected device. An exploit could allow the attacker to cause a stack overflow, which could allow the attacker to execute arbitrary code with administrative privileges, or to cause a process crash, which could result in a reload of the device and cause a DoS condition.
CVSS Score
8.8
EPSS Score
0.003
Published
2020-06-03
A vulnerability in the IPsec packet processor of Cisco IOS XR Software could allow an unauthenticated remote attacker to cause a denial of service (DoS) condition for IPsec sessions to an affected device. The vulnerability is due to improper handling of packets by the IPsec packet processor. An attacker could exploit this vulnerability by sending malicious ICMP error messages to an affected device that get punted to the IPsec packet processor. A successful exploit could allow the attacker to deplete IPsec memory, resulting in all future IPsec packets to an affected device being dropped by the device. Manual intervention is required to recover from this situation.
CVSS Score
5.8
EPSS Score
0.01
Published
2020-03-04
A vulnerability in the implementation of the Intermediate System–to–Intermediate System (IS–IS) routing protocol functionality in Cisco IOS XR Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition in the IS–IS process. The vulnerability is due to improper handling of a Simple Network Management Protocol (SNMP) request for specific Object Identifiers (OIDs) by the IS–IS process. An attacker could exploit this vulnerability by sending a crafted SNMP request to the affected device. A successful exploit could allow the attacker to cause a DoS condition in the IS–IS process.
CVSS Score
7.7
EPSS Score
0.012
Published
2020-01-26
A vulnerability in the implementation of the Intermediate System–to–Intermediate System (IS–IS) routing protocol functionality in Cisco IOS XR Software could allow an unauthenticated attacker who is in the same IS–IS area to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of crafted IS–IS link-state protocol data units (PDUs). An attacker could exploit this vulnerability by sending a crafted link-state PDU to an affected system to be processed. A successful exploit could allow the attacker to cause all routers within the IS–IS area to unexpectedly restart the IS–IS process, resulting in a DoS condition. This vulnerability affects Cisco devices if they are running a vulnerable release of Cisco IOS XR Software earlier than Release 6.6.3 and are configured with the IS–IS routing protocol. Cisco has confirmed that this vulnerability affects both Cisco IOS XR 32-bit Software and Cisco IOS XR 64-bit Software.
CVSS Score
7.4
EPSS Score
0.002
Published
2019-08-07
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.
CVSS Score
6.8
EPSS Score
0.006
Published
2019-07-06
A vulnerability in the Protocol Independent Multicast (PIM) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause the PIM process to restart, resulting in a denial of service condition on an affected device. The vulnerability is due to the incorrect processing of crafted AutoRP packets. An attacker could exploit this vulnerability by sending crafted packets to port UDP 496 on a reachable IP address on the device. A successful exploit could allow the attacker to cause the PIM process to restart. Software versions prior to 6.2.3, 6.3.2, 6.4.0, and 6.5.1 are affected.
CVSS Score
5.8
EPSS Score
0.003
Published
2019-04-17