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Vulnerability record · CVE-2026-18639 · published 11 August 2026

CVE-2026-18639: Authentication bypass by spoofing vulnerability

When Velociraptor is configured to use an OIDC IdP for authentication, it uses the email claim as a username. However, some IdP allow users to change the email claim without verification. Some IdPs do not set the "email_verified" claim and do not actually verify the email. This allows a user to impersonate another user by setting their email address within the IdP, allowing account takeover.

7.3 CVSS 3.1 High EPSS 0.39% · top 69.8% CWE-290 · Authentication bypass by spoofing Awaiting Analysis
7.3CVSS 3.1 base score
0.39%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
1References
28 Aug 2026Last modified by NVD

Description

When Velociraptor is configured to use an OIDC IdP for authentication, it uses the email claim as a username. However, some IdP allow users to change the email claim without verification. Some IdPs do not set the "email_verified" claim and do not actually verify the email. This allows a user to impersonate another user by setting their email address within the IdP, allowing account takeover.

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N

References

LinkTags
http://docs.velociraptor.app/announcements/advisories/cve-2026-18639/

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Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-18639), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.