Arista EOS NAT ACL Rule Filter access control

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.1$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Arista EOS. The impacted element is an unknown function of the component NAT ACL Rule Filter. The manipulation leads to access control. This vulnerability is referenced as CVE-2021-28511. The attack can only be performed from a local environment. No exploit is available.

Detailsinfo

A vulnerability was found in Arista EOS (the affected version is unknown). It has been rated as critical. This issue affects an unknown code of the component NAT ACL Rule Filter. The manipulation with an unknown input leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

This advisory documents the impact of an internally found vulnerability in Arista EOS for security ACL bypass. The impact of this vulnerability is that the security ACL drop rule might be bypassed if a NAT ACL rule filter with permit action matches the packet flow. This could allow a host with an IP address in a range that matches the range allowed by a NAT ACL and a range denied by a Security ACL to be forwarded incorrectly as it should have been denied by the Security ACL. This can enable an ACL bypass.

The weakness was published 08/05/2022. The advisory is shared at arista.com. The identification of this vulnerability is CVE-2021-28511 since 03/16/2021. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1068 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Vendor

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.1
VulDB Meta Temp Score: 6.1

VulDB Base Score: 5.9
VulDB Temp Score: 5.9
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CNA Base Score: 5.8
CNA Vector (Arista Networks, Inc.): 🔍

CVSSv2info

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

Exploitinginfo

Class: Access control
CWE: CWE-284 / CWE-266
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
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: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

03/16/2021 🔍
08/05/2022 +506 days 🔍
08/05/2022 +0 days 🔍
08/30/2022 +25 days 🔍

Sourcesinfo

Advisory: arista.com
Status: Confirmed

CVE: CVE-2021-28511 (🔍)
GCVE (CVE): GCVE-0-2021-28511
GCVE (VulDB): GCVE-100-205685

Entryinfo

Created: 08/05/2022 21:24
Updated: 08/30/2022 18:02
Changes: 08/05/2022 21:24 (37), 08/30/2022 18:02 (21)
Complete: 🔍
Cache ID: 216::103

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