Snapshot of public data from 31 Oct 2026, 12:50:06. This data is not updated until the API is deployed.

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CVE-2026-56191

Microsoft Exchange Online

HighCVSS 10.0 v3.1

Why this priority

?

Generic watch priority computed by public, versioned rules. It does not know your assets. See the glossary

  • Score CVSS critique (9.0 ou plus)

Description

This source does not allow its text to be republished here. Read the record at the source.

Affected products

VendorProductVersions
MicrosoftMicrosoft Exchange Online
  • -

Revision history

  1. Revision 2

  2. Revision 1

    New record

Qualification

CVSS severity
?

Technical severity score between 0 and 10, with its version (3.1, 4.0). See the glossary

10.0 CRITICAL CVSS v3.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C
KEV catalog
?

CISA catalog of vulnerabilities with confirmed exploitation. Absence from the catalog does not prove absence of exploitation. See the glossary

Unknown
Exploitation
Not reported
EPSS probability
?

Probability, between 0 and 1, that a vulnerability is exploited in the next 30 days, published daily by FIRST. Always dated. See the glossary

Unknown
Confidence
?

Quality of the sources behind the record. It is not a risk score. See the glossary

High

Priority rules, version 1

Record

Published on
24 July 2026
Weaknesses (CWE)
CWE-287

Sources

References

CVE-2026-56191 Microsoft Exchange Online · Avanguard TACTIC