Cisco IOS/IOS XE Split DNS Regular Expression incorrect regex

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.6$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Cisco IOS and IOS XE. This issue affects some unknown processing of the component Split DNS. This manipulation as part of Regular Expression causes incorrect regex. The identification of this vulnerability is CVE-2020-3408. It is possible to initiate the attack remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Cisco IOS and IOS XE (Router Operating System) (affected version unknown) and classified as problematic. Affected by this vulnerability is an unknown functionality of the component Split DNS. The manipulation as part of a Regular Expression leads to a incorrect regex vulnerability. The CWE definition for the vulnerability is CWE-185. The product specifies a regular expression in a way that causes data to be improperly matched or compared. As an impact it is known to affect availability. The summary by CVE is:

A vulnerability in the Split DNS feature of Cisco IOS Software and 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. The vulnerability occurs because the regular expression (regex) engine that is used with the Split DNS feature of affected releases may time out when it processes the DNS name list configuration. An attacker could exploit this vulnerability by trying to resolve an address or hostname that the affected device handles. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

The weakness was shared 09/24/2020 as cisco-sa-splitdns-SPWqpdGW as confirmed advisory (Website). The advisory is shared at tools.cisco.com. This vulnerability is known as CVE-2020-3408 since 12/12/2019. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/25/2020).

Upgrading eliminates this vulnerability.

The entry VDB-161870 is related to this item. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.9
VulDB Meta Temp Score: 6.8

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.6
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Incorrect regex
CWE: CWE-185 / CWE-697
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

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

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-splitdns-SPWqpdGW
Status: Confirmed

CVE: CVE-2020-3408 (🔍)
GCVE (CVE): GCVE-0-2020-3408
GCVE (VulDB): GCVE-100-161869
scip Labs: https://www.scip.ch/en/?labs.20150108
See also: 🔍

Entryinfo

Created: 09/25/2020 11:53
Updated: 09/25/2020 11:58
Changes: 09/25/2020 11:53 (41), 09/25/2020 11:58 (12)
Complete: 🔍
Cache ID: 216::103

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