CVE-2026-41100
published 2026-05-12CVE-2026-41100: Improper access control in M365 Copilot allows an authorized attacker to perform spoofing locally.
PriorityP421medium4.4CVSS 3.1
AVLACLPRLUINSUCLILAN
EPSS
0.25%
16.1th percentile
Improper access control in M365 Copilot allows an authorized attacker to perform spoofing locally.
Affected
7 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | 365_copilot | < 16.0.19822.20190 | 16.0.19822.20190 |
| microsoft | microsoft_365_copilot_for_android | >= 1.0 < 16.0.19822.20190 | 16.0.19822.20190 |
| microsoft | microsoft_excel_for_android | >= 16.0.0.0 < 16.0.19822.20190 | 16.0.19822.20190 |
| microsoft | microsoft_loop_for_android | >= 1.0.0 < 16.0.19822.20190 | 16.0.19822.20190 |
| microsoft | microsoft_onenote_for_android | >= 16.0.1 < 16.0.19822.20190 | 16.0.19822.20190 |
| microsoft | microsoft_powerpoint_for_android | >= 16.0.0.0 < 16.0.19822.20190 | 16.0.19822.20190 |
| microsoft | microsoft_word_for_android | >= 16.0.0.0 < 16.0.19822.20190 | 16.0.19822.20190 |
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VulDB
Microsoft 365 Copilot prior 16.0.19822.20190 on Android access control
vuldb·2026-05-12
CVE-2026-41100 [LOW] Microsoft 365 Copilot prior 16.0.19822.20190 on Android access control
A vulnerability classified as problematic has been found in Microsoft 365 Copilot on Android. The affected element is an unknown function. The manipulation leads to improper access controls.
This vulnerability is referenced as CVE-2026-41100. The attack can only be performed from a local environment. No exploit is available.
It is recommended to upgrade the affected component.
GHSA
GHSA-6gm9-cppw-hvx5: Improper access control in M365 Copilot allows an authorized attacker to perform spoofing locally
ghsa_unreviewed·2026-05-12
CVE-2026-41100 [MEDIUM] CWE-284 GHSA-6gm9-cppw-hvx5: Improper access control in M365 Copilot allows an authorized attacker to perform spoofing locally
Improper access control in M365 Copilot allows an authorized attacker to perform spoofing locally.
No detection rules found.
No public exploits indexed.
Hackernews
Microsoft 365 Android Apps Let Any App Steal Account Tokens via Leftover Debug Flag
blogs_hackernews·2026-06-03
CVE-2026-41100 Microsoft 365 Android Apps Let Any App Steal Account Tokens via Leftover Debug Flag
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## Microsoft 365 Android Apps Let Any App Steal Account Tokens via Leftover Debug Flag
A development flag left switched on in production builds of several Microsoft 365 Android apps disabled the check that limits account-token sharing to trusted Microsoft apps.
Any other app on the same phone could ask for the signed-in user's token and get it, then read email, open files, browse the calendar, and send messages as that user. No password, no login screen, no permission prompt.
Microsoft has patched it, and if you run Microsoft 365 apps on Android, update them.
The bug, which Enclave calls FlagLeft , hit Word, PowerPoint, Excel
Rapid7
Patch Tuesday - May 2026
blogs_rapid7·2026-05-13·CVSS 10.0
CVE-2026-41089 [CRITICAL] Patch Tuesday - May 2026
Microsoft is publishing 137 vulnerabilities on May 2026 Patch Tuesday . Microsoft is not aware of exploitation in the wild or public disclosure for any of these vulnerabilities. So far this month, Microsoft has provided patches to address 133 browser vulnerabilities, which are not included in the Patch Tuesday count above.
## Windows Netlogon: critical RCE
Anyone responsible for securing a domain controller should prioritize remediation of CVE-2026-41089 , which is a critical stack-based buffer overflow in Windows Netlogon with a CVSS v3 base score of 9.8. Exploitation leads to execution in the context of the Netlogon service, so that’s SYSTEM privileges on the domain controller. For most pentesters, that’s the point at which the customer report more or less writes itself. No privileges
Sans Isc
Microsoft May 2026 Patch Tuesday, (Tue, May 12th)
blogs_sans_isc·2026-05-12·CVSS 4.3
CVE-2026-41103 [MEDIUM] Microsoft May 2026 Patch Tuesday, (Tue, May 12th)
Microsoft May 2026 Patch Tuesday
Published: 2026-05-12. Last Updated: 2026-05-12 18:29:36 UTC
by Johannes Ullrich (Version: 1)
0 comment(s)
Today's Microsoft patch Tuesday fixes 137 different vulnerabilities. In addition, the update addresses 137 Chromium-related issues affecting Microsoft Edge.
There are no already disclosed or already exploited vulnerabilities included in today's patches. I removed the Chromium issues from the table below and included only the 137 Microsoft issues to make it more readable.
Note that issues related to Microsoft Azure are labeled as "no customer action required.
Significant Vulnerabilities of interest:
CVE-2026-41103: This vulnerability affects the Microsoft SSO Plugin for Jira & Confluence. Exploitation could lead to an elevation of privileges. Wit
2026-05-12
Published