CVE intelligence and bounded remediation

CVE-2026-27793 — Seerr is an open-source media request and discovery manager for Jellyfin, Plex, and Emby

Medium CVSS 6.5

Seerr is an open-source media request and discovery manager for Jellyfin, Plex, and Emby. Prior to version 3.1.0, the `GET /api/v1/user/:id` endpoint returns the full settings object for any user, including Pushover, Pushbullet, and Telegram credentials, to any authenticated requester regardless of their privilege level. This vulnerability can be exploited alone or combined with the reported unauthenticated account creation vulnerability, CVE-2026-27707. When combined, the two vulnerabilities create a zero-prior-access chain that leaks third-party API credentials for all users, including administrators. Version 3.1.0 contains a fix for both this vulnerability and for CVE-2026-27707.

Severity
Medium
CVSS
6.5 (3.1)
Published
2026-02-27
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-639

Affected products

  • seerr / seerr

Matched remediation archetype

Authorization bypass, IDOR, and cross-tenant access

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

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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