Vulnerability identifier: #VU51761

Vulnerability risk: Low

CVSSv3.1: 5.8 [CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-1375

CWE-ID: CWE-347

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Cisco IOS XE
Operating systems & Components / Operating system
Cisco Catalyst 3850 Series Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Catalyst 9300 Series Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Catalyst 9300L Series Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc

Vendor: Cisco Systems, Inc

Description

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

The vulnerability exists in the fast reload feature due to incorrect validations of parameters passed to a configuration file that is executed when the device boots up. A local administrator can tamper with a configuration file stored on a device, execute unsigned code at boot time and bypass the software image verification check.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco IOS XE: 16.12.1

Cisco Catalyst 3850 Series Switches: All versions

Cisco Catalyst 9300 Series Switches: All versions

Cisco Catalyst 9300L Series Switches: All versions

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External links
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fast-Zqr6DD5

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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.