CVE-2021-42306

Azure Active Directory vulnerability

CVSS

8.1

EPSS

3.1%

EPSS pct

86th

Exploited

No known

An information disclosure vulnerability manifests when a user or an application uploads unprotected private key data as part of an authentication certificate keyCredential on an Azure AD Application or Service Principal (which is not recommended). This vulnerability allows a user or service in the tenant with application read access to read the private key data that was added to the application. Azure AD addressed this vulnerability by preventing disclosure of any private key values added to the application. Microsoft has identified services that could manifest this vulnerability, and steps that customers should take to be protected. Refer to the FAQ section for more information. For more details on this issue, please refer to the MSRC Blog Entry.

Affected vendor

Microsoft

Affected product

Azure Active Directory

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Weakness type (CWE)

CWE-522 — Insufficiently Protected Credentials

Published

2021-11-24

Risk analysis

Based on its CVSS vector, this vulnerability is exploitable over the network, low attack complexity, requiring low privileges, no user interaction. Successful exploitation leads to high impact to confidentiality, high impact to integrity.

Its EPSS score of 3.1% reflects a lower probability of exploitation activity in the wild over the next 30 days, placing it above 86% of all scored CVEs.

Check your external exposure to CVE-2021-42306

Confirm whether Microsoft Azure Active Directory is running on any internet-facing host or subdomain.
Match discovered service fingerprints against the version affected by CVE-2021-42306.
Prioritise remediation if the asset is public, business-critical, or near authentication/payment flows.

How ThreatPort helps with CVE-2021-42306

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