CVE-2021-34767 – Cisco IOS XE Software for Catalyst 9800 Series Wireless Controllers IPv6 Denial of Service Vulnerability
https://notcve.org/view.php?id=CVE-2021-34767
A vulnerability in IPv6 traffic processing of Cisco IOS XE Wireless Controller Software for Cisco Catalyst 9000 Family Wireless Controllers could allow an unauthenticated, adjacent attacker to cause a Layer 2 (L2) loop in a configured VLAN, resulting in a denial of service (DoS) condition for that VLAN. The vulnerability is due to a logic error when processing specific link-local IPv6 traffic. An attacker could exploit this vulnerability by sending a crafted IPv6 packet that would flow inbound through the wired interface of an affected device. A successful exploit could allow the attacker to cause traffic drops in the affected VLAN, thus triggering the DoS condition. Una vulnerabilidad en el procesamiento del tráfico IPv6 de Cisco IOS XE Wireless Controller Software para Cisco Catalyst 9000 Family Wireless Controllers podría permitir a un atacante adyacente no autenticado causar un bucle de capa 2 (L2) en una VLAN configurada, resultando en una condición de denegación de servicio (DoS) para esa VLAN. • https://github.com/lukejenkins/CVE-2021-34767 https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewlc-ipv6-dos-NMYeCnZv • CWE-670: Always-Incorrect Control Flow Implementation •
CVE-2021-34729 – Cisco IOS XE SD-WAN Software Command Injection Vulnerability
https://notcve.org/view.php?id=CVE-2021-34729
A vulnerability in the CLI of Cisco IOS XE SD-WAN Software and Cisco IOS XE Software could allow an authenticated, local attacker to execute arbitrary commands with elevated privileges on an affected device. This vulnerability is due to insufficient validation of arguments passed to certain CLI commands. An attacker could exploit this vulnerability by including malicious input in the argument of an affected command. A successful exploit could allow the attacker to execute arbitrary commands with elevated privileges on the underlying operating system. An attacker would need valid user credentials to exploit this vulnerability. • https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ioxesdwan-clicmdinj-7bYX5k3 • CWE-77: Improper Neutralization of Special Elements used in a Command ('Command Injection') CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') •
CVE-2021-34705 – Cisco IOS and IOS XE Software FXO Interface Destination Pattern Bypass Vulnerability
https://notcve.org/view.php?id=CVE-2021-34705
A vulnerability in the Voice Telephony Service Provider (VTSP) service of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass configured destination patterns and dial arbitrary numbers. This vulnerability is due to insufficient validation of dial strings at Foreign Exchange Office (FXO) interfaces. An attacker could exploit this vulnerability by sending a malformed dial string to an affected device via either the ISDN protocol or SIP. A successful exploit could allow the attacker to conduct toll fraud, resulting in unexpected financial impact to affected customers. Una vulnerabilidad en el servicio Voice Telephony Service Provider (VTSP) de Cisco IOS Software y Cisco IOS XE Software podría permitir a un atacante remoto no autenticado omitir los patrones de destino configurados y marcar números arbitrarios. • https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fxo-pattern-bypass-jUXgygYv • CWE-232: Improper Handling of Undefined Values •
CVE-2021-34714 – Multiple Cisco Operating Systems Unidirectional Link Detection Denial of Service Vulnerability
https://notcve.org/view.php?id=CVE-2021-34714
A vulnerability in the Unidirectional Link Detection (UDLD) feature of Cisco FXOS Software, Cisco IOS Software, Cisco IOS XE Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause an affected device to reload. This vulnerability is due to improper input validation of the UDLD packets. An attacker could exploit this vulnerability by sending specifically crafted UDLD packets to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. Note: The UDLD feature is disabled by default, and the conditions to exploit this vulnerability are strict. • https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-nxos-xr-udld-dos-W5hGHgtQ • CWE-20: Improper Input Validation •
CVE-2021-34703 – Cisco IOS and IOS XE Software Link Layer Discovery Protocol Denial of Service Vulnerability
https://notcve.org/view.php?id=CVE-2021-34703
A vulnerability in the Link Layer Discovery Protocol (LLDP) message parser of Cisco IOS Software and Cisco IOS XE Software could allow an attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. This vulnerability is due to improper initialization of a buffer. An attacker could exploit this vulnerability via any of the following methods: An authenticated, remote attacker could access the LLDP neighbor table via either the CLI or SNMP while the device is in a specific state. An unauthenticated, adjacent attacker could corrupt the LLDP neighbor table by injecting specific LLDP frames into the network and then waiting for an administrator of the device or a network management system (NMS) managing the device to retrieve the LLDP neighbor table of the device via either the CLI or SNMP. An authenticated, adjacent attacker with SNMP read-only credentials or low privileges on the device CLI could corrupt the LLDP neighbor table by injecting specific LLDP frames into the network and then accessing the LLDP neighbor table via either the CLI or SNMP. • https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-lldp-dos-sBnuHSjT • CWE-456: Missing Initialization of a Variable CWE-665: Improper Initialization •