#VU80773 Improper Verification of Cryptographic Signature in Cisco Systems, Inc products - CVE-2023-20236

Vulnerability identifier: #VU80773

Vulnerability risk: Low

CVSSv4.0: 5.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2023-20236

CWE-ID: CWE-347

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Cisco IOS XR
Operating systems & Components / Operating system
Cisco 8000 Series Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco ASR 9000 Series Aggregation Services Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc
NCS 4000
Hardware solutions / Routers & switches, VoIP, GSM, etc
NCS 5000
Hardware solutions / Routers & switches, VoIP, GSM, etc
NCS 5700 Series Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Network Convergence System 1000 Series
Hardware solutions / Firmware
NCS540
Hardware solutions / Firmware
NCS5500
Hardware solutions / Firmware
NCS560
Hardware solutions / Firmware

Vendor: Cisco Systems, Inc

Description

The vulnerability allows a local user to compromise the target system.

The vulnerability exists due to insufficient image verification in the iPXE boot function. A local administrator can boot an unverified software image on the target device.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco IOS XR: 7.9, 7.10

Cisco 8000 Series Routers: All versions

Cisco ASR 9000 Series Aggregation Services Routers: All versions

Cisco Network Convergence System 1000 Series: All versions

NCS 4000: All versions

NCS 5000: All versions

NCS540: All versions

NCS5500: All versions

NCS560: All versions

NCS 5700 Series Routers: All versions

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External links
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-ipxe-sigbypass-pymfyqgB

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.