Denial of service in Cisco IOS XE software Layer 2 tunneling protocol

1) Error Handling

EUVDB-ID: #VU81249

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-20227

CWE-ID: CWE-388 - Error Handling

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper error handling in the Layer 2 Tunneling Protocol (L2TP) feature. A remote attacker can send specially crafted L2TP packets to the device and perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Cisco IOS XE: 17.3.6

Cisco 1000 Series Integrated Services Routers: All versions

1100 Series Integrated Services Routers: All versions

4000 Series Integrated Services Routers: All versions

Catalyst 8000V Edge Software: All versions

Catalyst 8200 Series Edge Platforms: All versions

Catalyst 8300 Series Edge Platforms: All versions

Catalyst 8500L Series Edge Platforms: All versions

Integrated Services Virtual Routers: All versions

VG400 Analog Voice Gateway : All versions

VG450 Analog Voice Gateway : All versions

VG420 Analog Voice Gateway: All versions

Cloud Services Routers 1000V Series: All versions

External links

http://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-xe-l2tp-dos-eB5tuFmV
http://bst.cloudapps.cisco.com/bugsearch/bug/CSCwe70596

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.