CVE-2021-26418 - Incorrect Authorization

Severity

71%

Complexity

27%

Confidentiality

70%

Microsoft SharePoint Spoofing Vulnerability This CVE ID is unique from CVE-2021-28478, CVE-2021-31172.

CVSS 3.1 Base Score 7.1. CVSS Attack Vector: network. CVSS Attack Complexity: low. CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N).

CVSS 2.0 Base Score 5.8. CVSS Attack Vector: network. CVSS Attack Complexity: medium. CVSS Vector: (AV:N/AC:M/Au:N/C:P/I:P/A:N).

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 SharePoint

First reported 3 years ago

2021-05-11 19:15:00

Last updated 3 years ago

2021-05-18 18:19:00

Affected Software

Microsoft SharePoint Foundation 2013 Service Pack 1

2013

Microsoft SharePoint Server 2019

2019

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