A bootloader vulnerability in Cisco NX-OS affects 100+ switches, allowing attackers to bypass image signature checks.———————————————————————————————————————Cisco released security patches for a vulnerability, tracked as CVE-2024-20397 (CVSS score of 5.2), in the NX-OS software’s bootloader that could be exploited by attackers to bypass image signature verification.*’A vulnerability in the bootloader of Cisco NX-OS Software could allow an unauthenticated attacker with physical access to an affected device, or an authenticated, local attacker with administrative credentials, to bypass NX-OS image signature verification.’ [reads](https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-image-sig-bypas-pQDRQvjL?vs_f=Cisco%20Security%20Advisory%26vs_cat=Security%20Intelligence%26vs_type=RSS%26vs_p=Cisco%20NX-OS%20Software%20Image%20Verification%20Bypass%20Vulnerability%26vs_k=1) the advisory.*The root cause of the vulnerability is insecure bootloader settings. An attacker could execute a series of bootloader commands to trigger the vulnerability.*’A successful exploit could allow the attacker to bypass NX-OS image signature verification and load unverified software.’ continues the advisory.*The vulnerability affects the following Cisco products running NX-OS Software with a vulnerable BIOS version, regardless of their configuration:* UCS 6500 Series Fabric Interconnects ([CSCwj35846](https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwj35846))* MDS 9000 Series Multilayer Switches ([CSCwh76163](https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwh76163))* Nexus 3000 Series Switches ([CSCwm47438](https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwm47438))* Nexus 7000 Series Switches ([CSCwh76166](https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwh76166))* Nexus 9000 Series Fabric Switches in ACI mode ([CSCwn11901](https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwn11901))* Nexus 9000 Series Switches in standalone NX-OS mode ([CSCwm47438](https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwm47438))* UCS 6400 Series Fabric Interconnects ([CSCwj35846](https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwj35846))The IT giant states that there are no workarounds that address this vulnerability.The company PSIRT is not aware of any attacks in the wild exploiting this vulnerability CVE-2024-20397Cisco will not address the vulnerability for Nexus 92160YC-X that has reached the End of Vulnerability/Security Support.Follow me on Twitter: [**@securityaffairs**](https://twitter.com/securityaffairs) and [**Facebook**](https://www.facebook.com/sec.affairs) and [Mastodon](https://infosec.exchange/@securityaffairs)[**Pierluigi Paganini**](http://www.linkedin.com/pub/pierluigi-paganini/b/742/559)**(** [**SecurityAffairs**](http://securityaffairs.co/wordpress/)**–** **hacking, NX-OS)**
Related Tags:
NAICS: 334 – Computer And Electronic Product Manufacturing
NAICS: 33 – Manufacturing – Metal
Electronics And Other
Blog: Security Affairs
Associated Indicators: