CVSS: 4.7EPSS: 0%CPEs: 312EXPL: 1CVE-2021-27853 – L2 network filtering can be bypassed using stacked VLAN0 and LLC/SNAP headers
https://notcve.org/view.php?id=CVE-2021-27853
Layer 2 network filtering capabilities such as IPv6 RA guard or ARP inspection can be bypassed using combinations of VLAN 0 headers and LLC/SNAP headers. Las capacidades de filtrado de la red de capa 2, como la protección IPv6 RA o la inspección ARP, pueden omitirse usando combinaciones de encabezados VLAN 0 y encabezados LLC/SNAP • https://blog.champtar.fr/VLAN0_LLC_SNAP https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08 https://kb.cert.org/vuls/id/855201 https://standards.ieee.org/ieee/802.1Q/10323 https://standards.ieee.org/ieee/802.2/1048 https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-VU855201-J3z8CKTX • CWE-290: Authentication Bypass by Spoofing •
CVSS: 7.2EPSS: 0%CPEs: 211EXPL: 0CVE-2019-1649 – Cisco Secure Boot Hardware Tampering Vulnerability
https://notcve.org/view.php?id=CVE-2019-1649
A vulnerability in the logic that handles access control to one of the hardware components in Cisco's proprietary Secure Boot implementation could allow an authenticated, local attacker to write a modified firmware image to the component. This vulnerability affects multiple Cisco products that support hardware-based Secure Boot functionality. The vulnerability is due to an improper check on the area of code that manages on-premise updates to a Field Programmable Gate Array (FPGA) part of the Secure Boot hardware implementation. An attacker with elevated privileges and access to the underlying operating system that is running on the affected device could exploit this vulnerability by writing a modified firmware image to the FPGA. A successful exploit could either cause the device to become unusable (and require a hardware replacement) or allow tampering with the Secure Boot verification process, which under some circumstances may allow the attacker to install and boot a malicious software image. • http://www.securityfocus.com/bid/108350 https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190513-secureboot https://www.kb.cert.org/vuls/id/400865 https://www.us-cert.gov/ics/advisories/icsa-20-072-03 • CWE-284: Improper Access Control CWE-667: Improper Locking •