CVE-2026-47645
CVE-2026-47645 is a high-severity vulnerability in Microsoft 365 Copilot with a CVSS 3.x base score of 8.8. 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-601.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- EPSS exploit prediction: 0% (33rd percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-38091
- Weakness: CWE-601
- Affected product: Microsoft 365 Copilot
- Published:
- Last modified:
Description
Url redirection to untrusted site ('open redirect') in Microsoft 365 Copilot's Business Chat allows an unauthorized attacker to elevate privileges over a network.
Frequently asked questions
- What is CVE-2026-47645?
- Url redirection to untrusted site ('open redirect') in Microsoft 365 Copilot's Business Chat allows an unauthorized attacker to elevate privileges over a network.
- How severe is CVE-2026-47645?
- CVE-2026-47645 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2026-47645 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-47645?
- CVE-2026-47645 affects Microsoft 365 Copilot. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-47645?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2026-47645 have an EU (EUVD) identifier?
- Yes. CVE-2026-47645 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-38091.
- When was CVE-2026-47645 published?
- CVE-2026-47645 was published on 2026-06-19 and last updated on 2026-06-26.
References
Affected products (1)
- cpe:2.3:a:microsoft:365_copilot:-:*:*:*:*:*:*:*
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Other CWE-601 (Open Redirect) vulnerabilities
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