Patch Forecast
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CVE-2026-63398

Coop is an open source review and moderation tool from ROOST

Risk score
44/100
CVSS
7.4 v4.0
Published
30 Oct 2026

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What to know

What it is
Coop is an open source review and moderation tool from ROOST. Prior to 1.0.2, the SAML strategy's verify callback resolved the authenticated user by email alone using kyselyUserFindByEmail, without binding the lookup to the organization in /saml/login/:orgId/callback. An attacker who administers an organization and co…
Affected
See advisory
Fix
Upgrade the product to 1.0.2 or later.
Exploitation
No known exploitation

Why it is Yellow

  • CVSS 7.4 high

References

Original description

Coop is an open source review and moderation tool from ROOST. Prior to 1.0.2, the SAML strategy's verify callback resolved the authenticated user by email alone using `kyselyUserFindByEmail`, without binding the lookup to the organization in `/saml/login/:orgId/callback`. An attacker who administers an organization and controls its SAML IdP signing key can submit an assertion for a victim email to another organization's callback when that target organization has registered the same signing certificate. The assertion verifies against the target certificate, and the email resolves to the target user, creating a session as that user and allowing full cross-tenant account takeover without privileges in the target organization. Exploitation requires the unusual configuration in which the target certificate matches a signing key controlled by the attacker. This issue is fixed in version 1.0.2.

Last activity 30 Oct 2026. Patch Forecast updates every hour.