Privilege escalation in Cisco IOS XR Software

Published: 2021-09-09

Risk	Low
Patch available	YES
Number of vulnerabilities	2
CVE-ID	CVE-2021-34719 CVE-2021-34728
CWE-ID	CWE-78
Exploitation vector	Local
Public exploit	N/A
Vulnerable software Subscribe	Cisco IOS XR Operating systems & Components / Operating system
Vendor	Cisco Systems, Inc

Security Bulletin

This security bulletin contains information about 2 vulnerabilities.

1) OS Command Injection

EUVDB-ID: #VU56432

Risk: Low

CVSSv3.1: 6.8 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-34719

CWE-ID: CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

Exploit availability: No

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to improper input validation in the CLI of Cisco IOS XR Software. A local user can run a specially crafted command to execute arbitrary code with root privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Cisco IOS XR: 6.8 - 7.4

External links

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-privescal-dZYMrKf
http://bst.cloudapps.cisco.com/bugsearch/bug/CSCvx48004

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.

2) OS Command Injection

EUVDB-ID: #VU56433