6.5
MEDIUM
CVE-2021-28511
Arista EOS Security ACL Bypass Vulnerability
Description

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.

INFO

Published Date :

Aug. 5, 2022, 5:15 p.m.

Last Modified :

Aug. 15, 2022, 8:50 p.m.

Source :

[email protected]

Remotely Exploitable :

Yes !

Impact Score :

2.5

Exploitability Score :

3.9
Affected Products

The following products are affected by CVE-2021-28511 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Arista eos
: Total Affected Vendor : 1 | Products : 1
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-28511.

URL Resource
https://www.arista.com/en/support/advisories-notices/security-advisory/15862-security-advisory-0078 Exploit Mitigation Vendor Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-28511 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-28511 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Initial Analysis by [email protected]

    Aug. 15, 2022

    Action Type Old Value New Value
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
    Changed Reference Type https://www.arista.com/en/support/advisories-notices/security-advisory/15862-security-advisory-0078 No Types Assigned https://www.arista.com/en/support/advisories-notices/security-advisory/15862-security-advisory-0078 Exploit, Mitigation, Vendor Advisory
    Added CWE NIST NVD-CWE-Other
    Added CPE Configuration AND OR *cpe:2.3:o:arista:eos:*:*:*:*:*:*:*:* versions up to (including) 4.24.9 *cpe:2.3:o:arista:eos:*:*:*:*:*:*:*:* versions from (including) 4.25.0 up to (including) 4.25.8 *cpe:2.3:o:arista:eos:*:*:*:*:*:*:*:* versions from (including) 4.26.0 up to (including) 4.26.5 *cpe:2.3:o:arista:eos:*:*:*:*:*:*:*:* versions from (including) 4.27.0 up to (including) 4.27.3 OR cpe:2.3:h:arista:7050cx3-32s:-:*:*:*:*:*:*:* cpe:2.3:h:arista:7050cx3m-32s:-:*:*:*:*:*:*:* cpe:2.3:h:arista:7050sx3-48c8:-:*:*:*:*:*:*:* cpe:2.3:h:arista:7050sx3-48yc:-:*:*:*:*:*:*:* cpe:2.3:h:arista:7050sx3-48yc12:-:*:*:*:*:*:*:* cpe:2.3:h:arista:7050sx3-48yc8:-:*:*:*:*:*:*:* cpe:2.3:h:arista:7050sx3-96yc8:-:*:*:*:*:*:*:* cpe:2.3:h:arista:7050tx3-48c8:-:*:*:*:*:*:*:* cpe:2.3:h:arista:720xp-24y6:-:*:*:*:*:*:*:* cpe:2.3:h:arista:720xp-24zy4:-:*:*:*:*:*:*:* cpe:2.3:h:arista:720xp-48y6:-:*:*:*:*:*:*:* cpe:2.3:h:arista:720xp-48zc2:-:*:*:*:*:*:*:* cpe:2.3:h:arista:720xp-96zc2:-:*:*:*:*:*:*:* cpe:2.3:h:arista:7300x3-32c:-:*:*:*:*:*:*:* cpe:2.3:h:arista:7300x3-48yc4:-:*:*:*:*:*:*:*
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-28511 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-28511 weaknesses.

CAPEC-19: Embedding Scripts within Scripts Embedding Scripts within Scripts CAPEC-441: Malicious Logic Insertion Malicious Logic Insertion CAPEC-478: Modification of Windows Service Configuration Modification of Windows Service Configuration CAPEC-479: Malicious Root Certificate Malicious Root Certificate CAPEC-502: Intent Spoof Intent Spoof CAPEC-503: WebView Exposure WebView Exposure CAPEC-536: Data Injected During Configuration Data Injected During Configuration CAPEC-546: Incomplete Data Deletion in a Multi-Tenant Environment Incomplete Data Deletion in a Multi-Tenant Environment CAPEC-550: Install New Service Install New Service CAPEC-551: Modify Existing Service Modify Existing Service CAPEC-552: Install Rootkit Install Rootkit CAPEC-556: Replace File Extension Handlers Replace File Extension Handlers CAPEC-558: Replace Trusted Executable Replace Trusted Executable CAPEC-562: Modify Shared File Modify Shared File CAPEC-563: Add Malicious File to Shared Webroot Add Malicious File to Shared Webroot CAPEC-564: Run Software at Logon Run Software at Logon CAPEC-578: Disable Security Software Disable Security Software
Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.10 }} 0.00%

score

0.38456

percentile

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
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