CVE-2021-42306

mediumpriority · track · 17EPSS 0.033 · 88 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

3.27% (88th) EPSS

CVSS 4 · medium

Is it mine?

12 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

8.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–high · 3.4–8.8

v2.04mediumAV:N/AC:L/Au:S/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 8 · impact 2.9

v2.03.4lowAV:N/AC:L/Au:S/C:P/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Nsecondary · NVD / NIST USexploitability 2.8 · impact 3.6

v3.18.8highAV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:Csecondary · ENISA EU

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Nsecondary · secure@microsoft.com USexploitability 2.8 · impact 5.2

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-522USprimaryCWE-287US

affected products (12)

Products and version ranges known to be affected.

Microsoft Azure Active Directory≤ N/Aenisa_euvdEU
Microsoft Azure Automation1.0.0 → publicationenisa_euvdEU
Microsoft Azure Migrate≤ N/Aenisa_euvdEU
Microsoft Azure Site Recovery≤ N/Aenisa_euvdEU
Microsoft Corp Azure Active Directoryall versionsfstec_bduRU
Microsoft Corp Azure Automationall versionsfstec_bduRU
Microsoft Corp Azure Migrateall versionsfstec_bduRU
Microsoft Corp Azure Site Recoveryall versionsfstec_bduRU
microsoft azure active directory< 2021-10-30nvdUScpe:2.3:a:microsoft:azure_active_directory:*:*:*:*:*:*:*:*
microsoft azure active site recovery< 2021-11-01nvdUScpe:2.3:a:microsoft:azure_active_site_recovery:*:*:*:*:*:*:*:*
microsoft azure automation< 2021-10-15nvdUScpe:2.3:a:microsoft:azure_automation:*:*:*:*:*:*:*:*
microsoft azure migrate< 2021-11-02nvdUScpe:2.3:a:microsoft:azure_migrate:*:*:*:*:*:*:*:*

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2021-11-24modified 2026-08-19

related (1,723)

Related entries.

ID	severity	EPSS	exploitable	published
CVE-2021-40655US	high7.5OT critical	86.7% (100th)	KEV	2021-09-24
An informtion disclosure issue exists in D-LINK-DIR-605 B2 Firmware Version : 2.01MT. An attacker can obtain a user name and password by forging a post request to the / getcfg.php…
CVE-2021-30116US	critical9.8OT critical	85.7% (100th)	KEV	2021-07-09
Kaseya VSA before 9.5.7 allows credential disclosure, as exploited in the wild in July 2021. By default Kaseya VSA on premise offers a download page where the clients for the insta…
CVE-2021-22681US	critical9.8OT critical	63.6% (99th)	KEV	2021-03-03
Rockwell Automation Studio 5000 Logix Designer Versions 21 and later, and RSLogix 5000 Versions 16 through 20 use a key to verify Logix controllers are communicating with Rockwell…
CVE-2020-29583US	critical9.8OT critical	90.2% (100th)	KEV	2020-12-22
Firmware version 4.60 of Zyxel USG devices contains an undocumented account (zyfwp) with an unchangeable password. The password for this account can be found in cleartext in the fi…
CVE-2017-9248US	critical9.8OT critical	75.1% (100th)	KEV	2017-07-03
Telerik.Web.UI.dll in Progress Telerik UI for ASP.NET AJAX before R2 2017 SP1 and Sitefinity before 10.0.6412.0 does not properly protect Telerik.Web.UI.DialogParametersEncryptionK…

+1718 more

references (7)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan