Cisco IOS XE up to 17.6.6 AUX signal handler with functionality that is not asynchronous-safe

CVSS Meta Temp Score
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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in Cisco IOS XE. This impacts an unknown function of the component AUX Handler. Executing a manipulation can lead to signal handler with functionality that is not asynchronous-safe. This vulnerability is tracked as CVE-2024-20309. The attack is restricted to local execution. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Cisco IOS XE and classified as problematic. This vulnerability affects an unknown functionality of the component AUX Handler. The manipulation with an unknown input leads to a signal handler with functionality that is not asynchronous-safe vulnerability. The CWE definition for the vulnerability is CWE-828. The product defines a signal handler that contains code sequences that are not asynchronous-safe, i.e., the functionality is not reentrant, or it can be interrupted. As an impact it is known to affect availability. CVE summarizes:

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.

The advisory is available at sec.cloudapps.cisco.com. This vulnerability was named CVE-2024-20309 since 11/08/2023. The exploitation appears to be easy. Local access is required to approach this attack. The technical details are unknown and an exploit is not available.

Upgrading eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CNA Base Score: 5.6
CNA Vector (Cisco Systems, Inc.): 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Signal handler with functionality that is not asynchronous-safe
CWE: CWE-828
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

11/08/2023 🔍
03/27/2024 +140 days 🔍
03/27/2024 +0 days 🔍
07/30/2025 +490 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-aux-333WBz8f
Status: Confirmed

CVE: CVE-2024-20309 (🔍)
GCVE (CVE): GCVE-0-2024-20309
GCVE (VulDB): GCVE-100-258322
scip Labs: https://www.scip.ch/en/?labs.20150108

Entryinfo

Created: 03/27/2024 18:26
Updated: 07/30/2025 16:34
Changes: 03/27/2024 18:26 (64), 05/06/2024 13:57 (1), 07/30/2025 16:34 (12)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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