CVE-2026-41100Public exploit

Local account token theft via enabled debug mode

Published May 12, 2026 · Updated May 12, 2026

Improper access control in Microsoft 365 Copilot for Android before 16.0.19822.20190 allows local users to steal account tokens. A production debug flag in the shared token-broker SDK skips the caller-authorization check and returns FOCI refresh tokens to untrusted Android apps. An attacker-controlled app must already run on the same signed-in device; stolen tokens permit account-data access and actions within the token's granted scope.

CVSS severity4.4
Medium
EPSS probability0.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in Microsoft 365 Copilot for Android before 16.0.19822.20190 allows local users to steal account tokens. A production debug flag in the shared token-broker SDK skips the caller-authorization check and returns FOCI refresh tokens to untrusted Android apps. An attacker-controlled app must already run on the same signed-in device; stolen tokens permit account-data access and actions within the token's granted scope.

The record

CVE
CVE-2026-41100
Published
May 12, 2026
Updated
May 12, 2026
Vendor
Microsoft
Product
Microsoft 365 Copilot app for Android
Classifications
CWE-284, T1528
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 12, 2026CVE publishedPublication date reported by the CVE source.
  2. May 12, 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=1.0 <16.0.19822.20190

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Microsoft · Microsoft 365 Copilot app for Androidversion=1.0 <16.0.19822.20190

Published CVSS scores

4.4MicrosoftCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/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.

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No observations available

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

Weakness, pattern, technique

CWE-284Improper Access Control
T1528Steal Application Access Token

Public exploit references

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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