#VU56832 Improper access control in Cisco Systems, Inc products - CVE-2021-34696

Vulnerability identifier: #VU56832

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-34696

CWE-ID: CWE-284

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
ASR 920 Series Aggregation Services Router
Other software / Other software solutions
Cisco ASR 9000 Series Aggregation Services Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco IOS XE
Operating systems & Components / Operating system

Vendor: Cisco Systems, Inc

Description

The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to incorrect programming of hardware when an ACL is configured using a method other than the configuration CLI. A remote attacker can bypass an ACL on the affected device.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

ASR 920 Series Aggregation Services Router: All versions

Cisco ASR 9000 Series Aggregation Services Routers: All versions

Cisco IOS XE: 17.3.2

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External links
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asr900acl-UeEyCxkv

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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