Cisco IOS/IOS XE Border Gateway Protocol BGP UPDATE input validation

CVSS Meta Temp Score
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability was found in Cisco IOS and IOS XE. It has been classified as problematic. Affected by this vulnerability is an unknown functionality of the component Border Gateway Protocol. This manipulation as part of BGP UPDATE causes input validation. This vulnerability is tracked as CVE-2020-3479. The attack is possible to be carried out remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability has been found in Cisco IOS and IOS XE (Router Operating System) (unknown version) and classified as problematic. Affected by this vulnerability is an unknown code block of the component Border Gateway Protocol. The manipulation as part of a BGP UPDATE leads to a input validation vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect availability. The summary by CVE is:

A vulnerability in the implementation of Multiprotocol Border Gateway Protocol (MP-BGP) for the Layer 2 VPN (L2VPN) Ethernet VPN (EVPN) address family in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of Border Gateway Protocol (BGP) update messages that contain crafted EVPN attributes. An attacker could exploit this vulnerability by sending BGP update messages with specific, malformed attributes to an affected device. A successful exploit could allow the attacker to cause an affected device to crash, resulting in a DoS condition.

The weakness was disclosed 09/24/2020 as cisco-sa-ios-bgp-evpn-dos-LNfY as confirmed advisory (Website). It is possible to read the advisory at tools.cisco.com. This vulnerability is known as CVE-2020-3479 since 12/12/2019. The exploitation appears to be difficult. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The pricing 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-161886 is pretty similar. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.9
VulDB Meta Temp Score: 4.8

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Input validation
CWE: CWE-20
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-ios-bgp-evpn-dos-LNfY
Status: Confirmed

CVE: CVE-2020-3479 (🔍)
GCVE (CVE): GCVE-0-2020-3479
GCVE (VulDB): GCVE-100-161887
scip Labs: https://www.scip.ch/en/?labs.20150108
See also: 🔍

Entryinfo

Created: 09/25/2020 13:22
Updated: 09/25/2020 13:27
Changes: 09/25/2020 13:22 (41), 09/25/2020 13:27 (12)
Complete: 🔍
Cache ID: 216::103

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