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Medium

Improper Authorization Information Disclosure in Microsoft Teams Events Portal

IdentifiersCVE-2026-33823CWE-285· Improper Authorization

CVE-2026-33823 is a Microsoft Teams Events Portal vulnerability caused by improper authorization. According to Microsoft, the flaw allows an authorized attacker with low privileges to exploit the service over the network, without user interaction, and disclose information. The associated CVSS v3.1 vector is AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N, indicating low-complexity remote exploitation, low privileges required, no user interaction, changed scope, high confidentiality impact, high integrity impact, and no availability impact. The issue affects Microsoft’s hosted service environment rather than customer-managed software deployments.

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ANALYST BRIEF

Impact, mitigation & remediation

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Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows an authenticated low-privilege attacker to access sensitive information in Microsoft Teams Events Portal over the network. Microsoft’s scoring also indicates high integrity impact and changed scope, suggesting the authorization failure may permit access or actions beyond the attacker’s intended security boundary. There is no indicated availability impact. Microsoft rated the issue Critical with a CVSS score of 9.6.

Mitigation

If you can’t patch tonight, do this now.

No customer mitigation is required. Microsoft reports the issue has already been fully mitigated in the hosted service, and users of Microsoft Teams do not need to take action.

Remediation

Patch, then assume compromise.

No customer remediation is required. Microsoft states the vulnerability was fixed in the service-side environment and has already been officially addressed by Microsoft.
PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
Microsoft CorporationTeamsapplication

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What this page doesn’t show

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Exposure mapping

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Threat actor evidence

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Associated malware

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Detection signatures

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Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity5

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