CVE-2026-41100
CVE-2026-41100 is a medium-severity vulnerability in Microsoft 365 Copilot with a CVSS 3.x base score of 4.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-284.
Key facts
- Severity: Medium (CVSS 3.x base score 4.4)
- EPSS exploit prediction: 0% (17th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-29686
- Weakness: CWE-284
- Affected product: Microsoft 365 Copilot
- Published:
- Last modified:
Description
Improper access control in M365 Copilot allows an authorized attacker to perform spoofing locally.
Frequently asked questions
- What is CVE-2026-41100?
- Improper access control in M365 Copilot allows an authorized attacker to perform spoofing locally.
- How severe is CVE-2026-41100?
- CVE-2026-41100 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
- Is CVE-2026-41100 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-41100?
- CVE-2026-41100 affects Microsoft 365 Copilot. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-41100?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- Does CVE-2026-41100 have an EU (EUVD) identifier?
- Yes. CVE-2026-41100 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29686.
- When was CVE-2026-41100 published?
- CVE-2026-41100 was published on 2026-05-12 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:microsoft:365_copilot:*:*:*:*:*:android:*:*
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