Vulnerability Database

346,508

Total vulnerabilities in the database

CVE-2022-20679 — cisco / ios_xe

Improper Input Validation

A vulnerability in the IPSec decryption routine of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to buffer exhaustion that occurs while traffic on a configured IPsec tunnel is being processed. An attacker could exploit this vulnerability by sending traffic to an affected device that has a maximum transmission unit (MTU) of 1800 bytes or greater. A successful exploit could allow the attacker to cause the device to reload. To exploit this vulnerability, the attacker may need access to the trusted network where the affected device is in order to send specific packets to be processed by the device. All network devices between the attacker and the affected device must support an MTU of 1800 bytes or greater. This access requirement could limit the possibility of a successful exploit.

  • Published: Apr 15, 2022
  • Updated: Nov 16, 2025
  • CVE: CVE-2022-20679
  • Severity: Medium
  • Exploit:

CVSS v3:

  • Severity: Medium
  • Score: 6.8
  • AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H

CVSS v2:

  • Severity: Medium
  • Score: 6.8
  • AV:N/AC:L/Au:S/C:N/I:N/A:C

CWEs:

Software From Fixed in
cisco / ios_xe 16.8.1 16.8.1.x
cisco / ios_xe 16.9.1 16.9.1.x
cisco / ios_xe 16.8.1a 16.8.1a.x
cisco / ios_xe 16.8.1s 16.8.1s.x
cisco / ios_xe 16.8.1b 16.8.1b.x
cisco / ios_xe 16.8.2 16.8.2.x
cisco / ios_xe 16.8.1d 16.8.1d.x
cisco / ios_xe 16.8.1c 16.8.1c.x
cisco / ios_xe 16.8.1e 16.8.1e.x
cisco / ios_xe 16.9.1s 16.9.1s.x
cisco / ios_xe 16.9.1c 16.9.1c.x
cisco / ios_xe 16.9.1b 16.9.1b.x
cisco / ios_xe 16.9.1d 16.9.1d.x
cisco / ios_xe 16.10.1 16.10.1.x
cisco / ios_xe 16.9.1a 16.9.1a.x
cisco / ios_xe 16.9.2a 16.9.2a.x
cisco / ios_xe 16.9.2 16.9.2.x
cisco / ios_xe 16.12.1 16.12.1.x
cisco / ios_xe 16.11.1 16.11.1.x
cisco / ios_xe 17.1.1 17.1.1.x
cisco / ios_xe 16.11.1a 16.11.1a.x
cisco / ios_xe 16.12.1c 16.12.1c.x
cisco / ios_xe 16.12.1t 16.12.1t.x
cisco / ios_xe 16.11.2 16.11.2.x
cisco / ios_xe 16.12.1s 16.12.1s.x
cisco / ios_xe 16.12.1a 16.12.1a.x
cisco / ios_xe 16.12.1x 16.12.1x.x
cisco / ios_xe 16.11.1c 16.11.1c.x
cisco / ios_xe 16.11.1b 16.11.1b.x
cisco / ios_xe 16.11.1s 16.11.1s.x
cisco / ios_xe 16.12.1w 16.12.1w.x
cisco / ios_xe 16.10.1s 16.10.1s.x
cisco / ios_xe 16.10.1d 16.10.1d.x
cisco / ios_xe 16.9.2s 16.9.2s.x
cisco / ios_xe 16.9.3h 16.9.3h.x
cisco / ios_xe 16.9.3a 16.9.3a.x
cisco / ios_xe 16.10.1a 16.10.1a.x
cisco / ios_xe 16.10.1f 16.10.1f.x
cisco / ios_xe 16.10.1g 16.10.1g.x
cisco / ios_xe 16.10.2 16.10.2.x
cisco / ios_xe 16.9.3 16.9.3.x
cisco / ios_xe 16.12.1y 16.12.1y.x
cisco / ios_xe 16.10.1e 16.10.1e.x
cisco / ios_xe 16.10.1b 16.10.1b.x
cisco / ios_xe 16.8.3 16.8.3.x
cisco / ios_xe 16.9.3s 16.9.3s.x
cisco / ios_xe 16.10.1c 16.10.1c.x
cisco / ios_xe 16.9.4 16.9.4.x
cisco / ios_xe 16.12.2 16.12.2.x
cisco / ios_xe 16.9.4c 16.9.4c.x
cisco / ios_xe 16.12.2a 16.12.2a.x
cisco / ios_xe 16.10.3 16.10.3.x
cisco / ios_xe 16.12.4 16.12.4.x
cisco / ios_xe 16.9.5 16.9.5.x
cisco / ios_xe 16.9.5f 16.9.5f.x
cisco / ios_xe 16.12.3 16.12.3.x
cisco / ios_xe 17.2.1 17.2.1.x
cisco / ios_xe 17.4.1 17.4.1.x
cisco / ios_xe 17.1.1s 17.1.1s.x
cisco / ios_xe 16.12.2t 16.12.2t.x
cisco / ios_xe 17.1.1a 17.1.1a.x
cisco / ios_xe 16.12.2s 16.12.2s.x
cisco / ios_xe 16.12.3a 16.12.3a.x
cisco / ios_xe 17.1.1t 17.1.1t.x
cisco / ios_xe 17.2.1a 17.2.1a.x
cisco / ios_xe 3.15.2xbs 3.15.2xbs.x
cisco / ios_xe 17.2.1v 17.2.1v.x
cisco / ios_xe 16.12.1z 16.12.1z.x
cisco / ios_xe 16.12.3s 16.12.3s.x
cisco / ios_xe 3.15.1xbs 3.15.1xbs.x
cisco / ios_xe 17.2.1r 17.2.1r.x
cisco / ios_xe 17.1.2 17.1.2.x
cisco / ios_xe 16.12.4a 16.12.4a.x
cisco / ios_xe 17.1.3 17.1.3.x
cisco / ios_xe 17.2.2 17.2.2.x
cisco / ios_xe 17.3.1 17.3.1.x
cisco / ios_xe 17.4.1a 17.4.1a.x
cisco / ios_xe 17.3.2 17.3.2.x
cisco / ios_xe 17.4.1b 17.4.1b.x
cisco / ios_xe 17.3.1a 17.3.1a.x
cisco / ios_xe 17.3.2a 17.3.2a.x
cisco / ios_xe 17.3.1w 17.3.1w.x
cisco / ios_xe 17.2.3 17.2.3.x
cisco / ios_xe 16.9.6 16.9.6.x
cisco / ios_xe 17.3.1x 17.3.1x.x
cisco / ios_xe 16.12.5 16.12.5.x
cisco / ios_xe 16.12.5b 16.12.5b.x
cisco / ios_xe 16.12.1z1 16.12.1z1.x
cisco / ios_xe 16.12.5a 16.12.5a.x
cisco / ios_xe 17.5.1 17.5.1.x
cisco / ios_xe 16.12.1z2 16.12.1z2.x
cisco / ios_xe 17.3.1z 17.3.1z.x
cisco / ios_xe 17.3.3 17.3.3.x
cisco / ios_xe 17.3.3a 17.3.3a.x
cisco / ios_xe 17.4.1c 17.4.1c.x
cisco / ios_xe 16.9.7 16.9.7.x
cisco / ios_xe 17.5.1a 17.5.1a.x
cisco / ios_xe 17.6.1 17.6.1.x
cisco / ios_xe 17.3.4a 17.3.4a.x
cisco / ios_xe 17.4.2 17.4.2.x
cisco / ios_xe 17.3.4b 17.3.4b.x
cisco / ios_xe 17.6.1a 17.6.1a.x
cisco / ios_xe 17.3.4c 17.3.4c.x
cisco / ios_xe 17.4.2a 17.4.2a.x
cisco / ios_xe 16.9.8 16.9.8.x
cisco / ios_xe 17.3.4 17.3.4.x
cisco / ios_xe 17.6.1w 17.6.1w.x
cisco / ios_xe 16.12.6a 16.12.6a.x
cisco / ios_xe 16.12.6 16.12.6.x

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.