CVE-2026-102893

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/zulip/zulip/commit/68d2d9defa39f8af96a50fc7430efc34dee120b5
https://github.com/zulip/zulip/commit/b40f191a8c71e74fcb471f71de6a1233de157102
https://github.com/zulip/zulip/pull/39913
https://github.com/zulip/zulip/releases/tag/12.2
https://github.com/zulip/zulip/security/advisories/GHSA-xw9h-9rcm-hx4m

Configurations

No configuration.

History

14 Oct 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-14 16:17

Updated : 2026-10-16 20:02

NVD link : CVE-2026-102893

Mitre link : CVE-2026-102893

CVE.ORG link : CVE-2026-102893

JSON object : View

Products Affected

No product.

CWE

CWE-287

Improper Authentication

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