CVE intelligence and bounded remediation

CVE-2020-27831 — Redhat Quay security vulnerability

Medium CVSS 4.3

A flaw was found in Red Hat Quay, where it does not properly protect the authorization token when authorizing email addresses for repository email notifications. This flaw allows an attacker to add email addresses they do not own to repository notifications.

Severity
Medium
CVSS
4.3 (3.1)
Published
2021-05-27
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-284, CWE-522

Affected products

  • redhat / quay

Matched remediation archetype

Authorization bypass, IDOR, and cross-tenant access

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Check exposure

  • Map object and action authorization checks across API, UI, batch, import/export, and background-job paths.
  • Identify tenant, ownership, role, and policy boundaries for affected resources and administrative operations.
  • Use synthetic fixtures to compare intended access matrices without accessing another user's real data.

Remediate safely

  • Enforce server-side authorization at each resource access and state transition using the authenticated principal and trusted tenant context.
  • Scope data queries by tenant and ownership; treat client-supplied identifiers, roles, and policy claims as untrusted.
  • Add deny-by-default policy tests for horizontal and vertical access across every affected transport.

Authoritative sources

Complete CVE record and remediation plan

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