Vulnerability identifier: #VU56835

Vulnerability risk: Low

CVSSv3.1: 5.2 [CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-34724

CWE-ID: CWE-284

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Cisco IOS XE SD-WAN
Other software / Other software solutions
Cisco 1000 Series Integrated Services Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco 4000 Series Integrated Services Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco ASR 1000 Series Aggregation Services Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Cloud Services Router 1000V Series
Hardware solutions / Routers & switches, VoIP, GSM, etc

Vendor: Cisco Systems, Inc

Description

The vulnerability allows a local user to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to insufficient file system protection and the presence of a sensitive file in the bootflash directory. A local administrator can overwrite an installer file stored in the bootflash directory with arbitrary commands to read and write changes to the configuration database on the affected device.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco IOS XE SD-WAN: 17.3.1a

Cisco 1000 Series Integrated Services Routers: All versions

Cisco 4000 Series Integrated Services Routers: All versions

Cisco ASR 1000 Series Aggregation Services Routers: All versions

Cisco Cloud Services Router 1000V Series: All versions

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External links
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxesdwan-privesc-VP4FG3jD

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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.