CVE-2026-33823Network attack vector

Authenticated disclosure of protected portal information

Published May 7, 2026 · Updated May 7, 2026

Improper authorization in Microsoft Teams allows remote authenticated users to disclose information through the Microsoft Team Events Portal. Microsoft identifies the affected locus but has not disclosed which authorization check the portal omits or enforces incorrectly. A valid Teams identity is required, and the public record does not identify the exposed data or establish a direct availability impact.

CVSS severity9.6
Critical
EPSS probability0.72%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in Microsoft Teams allows remote authenticated users to disclose information through the Microsoft Team Events Portal. Microsoft identifies the affected locus but has not disclosed which authorization check the portal omits or enforces incorrectly. A valid Teams identity is required, and the public record does not identify the exposed data or establish a direct availability impact.

The record

CVE
CVE-2026-33823
Published
May 7, 2026
Updated
May 7, 2026
Vendor
Microsoft
Product
Microsoft Teams
Classifications
CWE-285
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 7, 2026CVE publishedPublication date reported by the CVE source.
  2. May 7, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=-

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Microsoft · Microsoft Teamsversion=-

Published CVSS scores

9.6Microsoft CorporationCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-285Improper Authorization

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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