CVE-2026-83947

mediumpriority · track · 26OT risk · elevatedEPSS 0.005 · 44 %ileDENLRUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.53% (44th) EPSS

CVSS 6.5 · medium

Is it mine?

18 products

Check your exposure

Who says so?

5 sources

fstec_bdu · cert_bund · msrc_csaf · ncsc_nl

EPSS · scored 2026-10-27

Missing authorization in Azure Event Grid allows an authorized attacker to perform spoofing over a network.

cvss

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

7.7

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6–7.7

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

v3.17.7highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:Nprimary · secure@microsoft.com USexploitability 3.1 · impact 4

v3.17.7highAV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:Nsecondary · FSTEC (BDU) RU

v3.16mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

v3.17.7highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N/E:U/RL:O/RC:Csecondary · NCSC-NL NL

v3.17.7highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N/E:U/RL:O/RC:Csecondary · Microsoft Security Response Center US

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-862USCWE-862USCWE-862USCWE-862USCWE-862US

affected products (18)

Products and version ranges known to be affected.

Microsoft Azure Event Grid Systemall versionscert_bundDEcpe:/a:microsoft:azure:event_grid_system
Microsoft Corp Azure Event Gridall versionsfstec_bduRU
Microsoft Azure Event Grid Systemall versionsfixedmsrc_csafUS
Microsoft Arc Enabled Servers - Azure Connected Machine Agent≤ vers:unknown/*ncsc_nlNL
Microsoft Azure≤ vers:unknown/*ncsc_nlNL
Microsoft Azure API Center≤ vers:unknown/*ncsc_nlNL
Microsoft Azure CLI≤ vers:unknown/*ncsc_nlNL
Microsoft Azure Container Storage enabled by Azure Arc≤ vers:unknown/*ncsc_nlNL
Microsoft Azure CycleCloud 8.9.1≤ vers:unknown/*ncsc_nlNL
Microsoft Azure CycleCloud 8.9.2≤ vers:unknown/*ncsc_nlNL
Microsoft Azure DevOps CLI Extension≤ vers:unknown/*ncsc_nlNL
Microsoft Azure Event Grid System≤ vers:unknown/*ncsc_nlNL
Microsoft Azure Key Vault Client SDK≤ vers:unknown/*ncsc_nlNL
Microsoft Azure SRE Agent≤ vers:unknown/*ncsc_nlNL
Microsoft Azure Storage Blobs client library for Java≤ vers:unknown/*ncsc_nlNL
Microsoft Microsoft Bookings≤ vers:unknown/*ncsc_nlNL
Microsoft Microsoft Partner Center≤ vers:unknown/*ncsc_nlNL
microsoft azure event gridall versionsnvdUScpe:2.3:a:microsoft:azure_event_grid:*:*:*:*:*:*:*:*

advisories (3)

Vendor and ecosystem advisories describing this.

NCSC-2026-0421Kwetsbaarheden verholpen in Microsoft AzureNL2026-10-13csaf · ncsc_nlNL
Microsoft heeft kwetsbaarheden verholpen in diverse Azure componenten, zoals Key Vault, DevOps, API center en Storage.
WID-SEC-W-2026-3834Microsoft Azure: Mehrere SchwachstellenDeutsch2026-10-08csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in verschiedenen Microsoft Azure Komponenten ausnutzen, um seine Privilegien zu erhöhen, beliebigen Code auszuführen, Spoofing-Angriffe durchzuführen oder Informationen offenzulegen.
msrc_CVE-2026-83947Azure Event Grid Spoofing Vulnerability2026-10-08csaf · msrc_csafUS
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

also known as (1)

Other names and identifiers for this entity.

BDU:2026-16748 fstec_bdu

sources

Which sources assert this record, and when.

fstec_bdu cert_bund msrc_csaf ncsc_nl nvd NVD CVE.org MITRE

published 2026-10-08modified 2026-10-19

references (1) nvd

External citations — patches, advisories, analysis.

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83947Vendor Advisory

scry

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