Coop has SAML cross-tenant authentication bypass
CVSS score
7.4
EPSS probability
—
Risk score
0.7
Published
1 h ago
Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.
Impact on My Inventory
Only the personal products you have added to your account are assessed; an organisation's inventory does not appear here.
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Vulnerability description
DayBreach AI Explanation
Verified against sourcesSources read
1
Source agreement
Tam uyum
Evidence confidence
%55
Short explanation
Roost open source Coop review and moderation tool contains an authentication bypass vulnerability because the SAML strategy's verify callback resolves authenticated users by email alone without binding the lookup to the organization.
This vulnerability allows attackers to perform a full cross-tenant account takeover in the target organization without requiring any privileges.
What should be done?
- Update to version 1.0.2 or later
- Follow vendor advisories
Chain of evidence and sources
Coop 1.0.2 öncesi sürümlerde SAML doğrulaması kullanıcıları organizasyona bağlamadan yalnızca e-posta ile çözmektedir.
Zafiyetin istismarı, hedef sertifikanın saldırganın kontrol ettiği bir imzalama anahtarıyla eşleştiği yapılandırmayı gerektirir.
Show the technical text from the sources
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.
CVSS vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
CWE: CWE-287
This explanation was compiled automatically from the source records. Scores, active exploitation, patch and exploit status come straight from the sources.
IMPACT: Affected Products and Software
Affected Products
The following products are affected by CVE-2026-63398 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.
| ID | VENDOR | PRODUCT | ACTION |
|---|---|---|---|
| 1 | roostorg | coop | View |
RED HAT CSAF/VEX: Product Impact Check
SCORING: CVSS from Multiple Sources
CVSS Scores
The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.
| SCORE | VERSION | SEVERITY | VECTOR | SOURCE |
|---|---|---|---|---|
| 7.4 | CVSS V4_0 | HIGH | CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N | CVE CNA |
| 7.4 | CVSS V40 | HIGH | CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X | NVD |
Patch and Remediation Guide
Solution & Remediation Advisory
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Public exploit and active exploitation status
Verified exploit intelligence
No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.
Weakness Classification and Attack Patterns (CWE & CAPEC)
CWE - Common Weakness Enumeration
While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-63398 is associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-63398 weaknesses.
Attack Vector and Accessibility
Official Sources and Advisories
Similar Vulnerabilities
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