Cisco IOS/IOS XE ISDN Subsystem Messages input validation

CVSS Meta Temp Score
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CTI Interest Score
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5.8$0-$5k0.00

A vulnerability classified as problematic has been found in Cisco IOS and IOS XE (Router Operating System) (unknown version). This affects an unknown code block of the component ISDN Subsystem. The manipulation as part of a Messages leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on availability. The summary by CVE is:

A vulnerability in the ISDN subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient input validation when the ISDN Q.931 messages are processed. An attacker could exploit this vulnerability by sending a malicious ISDN Q.931 message to an affected device. A successful exploit could allow the attacker to cause the process to crash, resulting in a reload of the affected device.

The weakness was released 09/24/2020 as cisco-sa-iosxe-isdn-q931-dos-6 as confirmed advisory (Website). The advisory is shared at tools.cisco.com. This vulnerability is uniquely identified as CVE-2020-3511 since 12/12/2019. Access to the local network is required for this attack. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

Upgrading eliminates this vulnerability.

Entry connected to this vulnerability is available at 161902.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
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CVSSv3info

VulDB Meta Base Score: 6.0
VulDB Meta Temp Score: 5.9

VulDB Base Score: 4.7
VulDB Temp Score: 4.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.4
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Input validation
CWE: CWE-20
ATT&CK: Unknown

Local: No
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/12/2019 🔍
09/24/2020 +287 days 🔍
09/25/2020 +1 days 🔍
09/25/2020 +0 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-iosxe-isdn-q931-dos-6
Status: Confirmed

CVE: CVE-2020-3511 (🔍)
scip Labs: https://www.scip.ch/en/?labs.20150108
See also: 🔍

Entryinfo

Created: 09/25/2020 13:27
Updated: 09/25/2020 13:32
Changes: 09/25/2020 13:27 (41), 09/25/2020 13:32 (12)
Complete: 🔍

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