Skip to content
Sign in
8.6 High

CVE-2023-20227 A vulnerability in the Layer 2 Tunneling Protocol (L2TP) feature of Cisco IOS XE Software could allow an…

Description

A vulnerability in the Layer 2 Tunneling Protocol (L2TP) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper handling of certain L2TP packets. An attacker could exploit this vulnerability by sending crafted L2TP packets to an affected device. A successful exploit could allow the attacker to cause the device to reload unexpectedly, resulting in a DoS condition. Note: Only traffic directed to the affected system can be used to exploit this vulnerability.

Affected products and versions

Product Affected versions Fixed in
Cisco IOS XE Software 17.5 17.5.1c → 17.5.1 No fix stated
Cisco IOS XE Software 17.4 17.4.1a → 17.4.2 No fix stated
Cisco IOS XE Software 17.3 17.3.1w → 17.3.7 No fix stated
Cisco IOS XE Software 17.2 17.2.1r → 17.2.3 No fix stated
Cisco IOS XE Software 17.1 17.1.1s → 17.1.3 No fix stated
Cisco IOS XE Software 16.12 16.12.1s → 16.12.10a No fix stated
Cisco IOS XE Software 16.11 16.11.1s → 16.11.2 No fix stated
Cisco IOS XE Software 16.10 16.10.1s → 16.10.3 No fix stated
Cisco IOS XE Software 16.9 16.9.1s → 16.9.8 No fix stated
Show the other branch
Product Affected versions Fixed in
Cisco IOS XE Software 16.8 16.8.1s → 16.8.3 No fix stated

Other CVEs of Cisco IOS XE Software

The 248 CVEs of Cisco IOS XE Software →
CVE-2026-20311 A vulnerability in the web-based management interface of Cisco IOS XE Software could allow an authenticated, remote… 6.3 Medium CVE-2026-20301 A vulnerability in the Extensible Messaging Client Protocol (XMCP), also referred to as the External Client protocol, of… 8.6 High CVE-2026-20308 A vulnerability in the web-based management interface of Cisco IOS XE Software could allow an authenticated, remote… 4.3 Medium CVE-2026-20273 As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XE Software engineering… 8.6 High
Track this CVE