CVE-2024-20309
MEDIUMDescription
A vulnerability in auxiliary asynchronous port (AUX) functions of Cisco IOS XE Software could allow an authenticated, local attacker to cause an affected device to reload or stop responding. This vulnerability is due to the incorrect handling of specific ingress traffic when flow control hardware is enabled on the AUX port. An attacker could exploit this vulnerability by reverse telnetting to the AUX port and sending specific data after connecting. A successful exploit could allow the attacker to cause the device to reset or stop responding, resulting in a denial of service (DoS) condition.
Is your site exposed to CVE-2024-20309?
Run a free security scan — no signup, results in seconds.
CVSS v3.1 Score
5.6
MEDIUM
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H
Weakness Type (CWE)
CWE-828
CWE-828
Affected Products
| Vendor | Product |
|---|---|
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
| cisco | ios_xe |
References
Frequently Asked Questions
What is CVE-2024-20309? +
A vulnerability in auxiliary asynchronous port (AUX) functions of Cisco IOS XE Software could allow an authenticated, local attacker to cause an affected device to reload or stop responding.
This vulnerability is due to the incorrect handling of specific ingress traffic when flow control hardware is enabled on the AUX port. An attacker could exploit this vulnerability by reverse telnetting to the AUX port and sending specific data after connecting. A successful exploit could allow the attacker to cause the device to reset or stop responding, resulting in a denial of service (DoS) condition. It has a CVSS v3.1 base score of 5.6 (MEDIUM).
How severe is CVE-2024-20309? +
CVE-2024-20309 has a CVSS v3.1 score of 5.6 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
What products are affected by CVE-2024-20309? +
CVE-2024-20309 affects products from cisco, specifically: ios_xe. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2024-20309? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.
Related Vulnerabilities
CVE-2024-25742
6.5
In the Linux kernel before 6.9, an untrusted hypervisor can inject virtual interrupt 29 (#VC) at any point in time …
CVE-2025-20281
10.0
A vulnerability in a specific API of Cisco ISE and Cisco ISE-PIC could allow an unauthenticated, remote attacker to execute …
CVE-2025-20282
10.0
A vulnerability in an internal API of Cisco ISE and Cisco ISE-PIC could allow an unauthenticated, remote attacker to upload …
CVE-2024-20419
10.0
A vulnerability in the authentication system of Cisco Smart Software Manager On-Prem (SSM On-Prem) could allow an unauthenticated, remote attacker …
CVE-2025-20188
10.0
A vulnerability in the Out-of-Band Access Point (AP) Image Download, the Clean Air Spectral Recording, and the client debug bundles …
CVE-2026-20182
10.0
May 2026: This security advisory provides the details and fix information for a vulnerability that was discovered and fixed after …