Microsoft 365 Copilot Elevation of Privilege Vulnerability

published 2026-04-23 6 mo ago modified 2026-10-26 13 d ago also EUVD-2026-25310

cvss: 9.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 34%
public exploits: 0; none known

Url redirection to untrusted site ('open redirect') in M365 Copilot allows an unauthorized attacker to elevate privileges over a network.

Patch / fix

links 1

msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33102 advisory

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 6 mo ago (2026-04-24)

Exploit prediction

0.40% chance of exploitation in the next 30 days, higher than 34% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	9.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N/E:U/RL:O/RC:C
CNA	3.1	9.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

Affected products

Microsoft Microsoft 365 Copilot

Classification

Weakness

CWE-601 URL Redirection to Untrusted Site

References

msrc.microsoft.com /update-guide/vulnerability/CVE-2026-33102
vendor-advisory, patch

Sources

CVE List CVE-2026-33102
NVD CVE-2026-33102

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary