CVE-2026-33102
CVE-2026-33102 is a critical-severity vulnerability in Microsoft 365 Copilot with a CVSS 3.x base score of 9.3. 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: Critical (CVSS 3.x base score 9.3)
- EPSS exploit prediction: 0% (32nd percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-25310
- Weakness: CWE-601
- Affected product: Microsoft 365 Copilot
- Published:
- Last modified:
Description
Url redirection to untrusted site ('open redirect') in M365 Copilot allows an unauthorized attacker to elevate privileges over a network.
Frequently asked questions
- What is CVE-2026-33102?
- Url redirection to untrusted site ('open redirect') in M365 Copilot allows an unauthorized attacker to elevate privileges over a network.
- How severe is CVE-2026-33102?
- CVE-2026-33102 has a CVSS 3.x base score of 9.3, rated critical 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 none.
- Is CVE-2026-33102 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-33102?
- CVE-2026-33102 affects Microsoft 365 Copilot. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-33102?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- Does CVE-2026-33102 have an EU (EUVD) identifier?
- Yes. CVE-2026-33102 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25310.
- When was CVE-2026-33102 published?
- CVE-2026-33102 was published on 2026-04-23 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:microsoft:365_copilot:-:*:*:*:*:*:*:*
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Other CWE-601 (Open Redirect) vulnerabilities
- CVE-2018-3774 — Critical (CVSS 10.0): Incorrect parsing in url-parse <1.4.3 returns wrong hostname which leads to multiple vulnerabilities such as SSRF, Open…
- CVE-2019-25282 — Critical (CVSS 9.8): V-SOL GPON/EPON OLT Platform v2.03 contains an open redirect vulnerability in the script that allows attackers to…
- CVE-2020-36912 — Critical (CVSS 9.8): Plexus anblick Digital Signage Management 3.1.13 contains an open redirect vulnerability in the 'PantallaLogin' script…
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