CVE-2026-102893 (GCVE-0-2026-102893)
Vulnerability from cvelistv5
Published
2026-10-14 15:49
Modified
2026-10-15 19:06
CWE
  • CWE-287 - Improper Authentication
Summary
Zulip is an open-source team collaboration tool. In Zulip Server versions through 12.1, GenericOpenIdConnectBackend matches the identity provider email claim to an active account's delivery_email without rejecting an explicitly false email_verified claim. If a configured identity provider returns an email address that the authenticating user does not control together with email_verified=false, Zulip can log the user into the existing account for that address. Exploitation requires a misconfigured trusted identity provider, and deployments whose authoritative identity provider only emits email addresses controlled by the authenticating user are not affected. This issue is fixed in version 12.2.
Impacted products
Vendor Product Version
zulip zulip Version: < 12.2
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Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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