CVE-2021-42292 - Incorrect Authorization

Severity

78%

Complexity

18%

Confidentiality

98%

Microsoft Excel Security Feature Bypass Vulnerability

CVSS 3.1 Base Score 7.8. CVSS Attack Vector: local. CVSS Attack Complexity: low. CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

CVSS 2.0 Base Score 6.8. CVSS Attack Vector: network. CVSS Attack Complexity: medium. CVSS Vector: (AV:N/AC:M/Au:N/C:P/I:P/A:P).

Demo Examples

Incorrect Authorization

CWE-863

The following code could be for a medical records application. It displays a record to already authenticated users, confirming the user's authorization using a value stored in a cookie.


               
}
}
setcookie("role", $role, time()+60*60*2);
die("\n");
DisplayMedicalHistory($_POST['patient_ID']);
die("You are not Authorized to view this record\n");

The programmer expects that the cookie will only be set when getRole() succeeds. The programmer even diligently specifies a 2-hour expiration for the cookie. However, the attacker can easily set the "role" cookie to the value "Reader". As a result, the $role variable is "Reader", and getRole() is never invoked. The attacker has bypassed the authorization system.

Overview

Type

Microsoft

First reported 3 years ago

2021-11-10 01:19:00

Last updated 3 years ago

2021-11-10 18:22:00

Affected Software

Microsoft 365 Apps Enterprise Edition

Microsoft Excel 2013 Service Pack 1

2013

Microsoft Excel 2013 Service Pack 1 Runtime Edition

2013

Microsoft Office 2013 SP1

2013

Microsoft Office 2013 Service Pack 1 RT Edition

2013

Microsoft Office 2016

2016

Microsoft Office 2019

2019
-

Microsoft Office 2019 for macOS

2019
macos

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