{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-27707", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-02-23T17:56:51.203Z", "datePublished": "2026-02-27T19:29:18.768Z", "dateUpdated": "2026-02-27T20:22:24.091Z"}, "containers": {"cna": {"title": "Plex-configured Seerr instances vulnerable to unauthenticated account registration via Jellyfin authentication endpoint", "problemTypes": [{"descriptions": [{"cweId": "CWE-288", "lang": "en", "description": "CWE-288: Authentication Bypass Using an Alternate Path or Channel", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-807", "lang": "en", "description": "CWE-807: Reliance on Untrusted Inputs in a Security Decision", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 7.3, "baseSeverity": "HIGH", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L", "version": "3.1"}}], "references": [{"name": "https://github.com/seerr-team/seerr/security/advisories/GHSA-rc4w-7m3r-c2f7", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/seerr-team/seerr/security/advisories/GHSA-rc4w-7m3r-c2f7"}, {"name": "https://github.com/seerr-team/seerr/commit/4ae20684092b5b28527b23dfbc1a3417858fee8e", "tags": ["x_refsource_MISC"], "url": "https://github.com/seerr-team/seerr/commit/4ae20684092b5b28527b23dfbc1a3417858fee8e"}, {"name": "https://github.com/seerr-team/seerr/releases/tag/v3.1.0", "tags": ["x_refsource_MISC"], "url": "https://github.com/seerr-team/seerr/releases/tag/v3.1.0"}], "affected": [{"vendor": "seerr-team", "product": "seerr", "versions": [{"version": ">= 2.0.0, < 3.1.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-02-27T19:32:07.180Z"}, "descriptions": [{"lang": "en", "value": "Seerr is an open-source media request and discovery manager for Jellyfin, Plex, and Emby. Starting in version 2.0.0 and prior to version 3.1.0, an authentication guard logic flaw in `POST /api/v1/auth/jellyfin` allows an unauthenticated attacker to register a new Seerr account on any Plex-configured instance by authenticating with an attacker-controlled Jellyfin server. The attacker receives an authenticated session and can immediately use the application with default permissions, including the ability to submit media requests to Radarr/Sonarr. Any Seerr deployment where all three of the following are true may be vulnerable: `settings.main.mediaServerType` is set to `PLEX` (the most common deployment).; `settings.jellyfin.ip` is set to `\"\"` (default, meaning Jellyfin was never configured); and `settings.main.newPlexLogin` is set to `true` (default). Jellyfin-configured and Emby-configured deployments are not affected. Version 3.1.0 of Seerr fixes this issue."}], "source": {"advisory": "GHSA-rc4w-7m3r-c2f7", "discovery": "UNKNOWN"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-02-27T20:22:11.831766Z", "id": "CVE-2026-27707", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-02-27T20:22:24.091Z"}}]}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "Seerr is an open-source media request and discovery manager for Jellyfin, Plex, and Emby. Starting in version 2.0.0 and prior to version 3.1.0, an authentication guard logic flaw in `POST /api/v1/auth/jellyfin` allows an unauthenticated attacker to register a new Seerr account on any Plex-configured instance by authenticating with an attacker-controlled Jellyfin server. The attacker receives an authenticated session and can immediately use the application with default permissions, including the ability to submit media requests to Radarr/Sonarr. Any Seerr deployment where all three of the following are true may be vulnerable: `settings.main.mediaServerType` is set to `PLEX` (the most common deployment).; `settings.jellyfin.ip` is set to `\"\"` (default, meaning Jellyfin was never configured); and `settings.main.newPlexLogin` is set to `true` (default). Jellyfin-configured and Emby-configured deployments are not affected. Version 3.1.0 of Seerr fixes this issue."}], "id": "CVE-2026-27707", "lastModified": "2026-02-27T20:21:38.760", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 7.3, "baseSeverity": "HIGH", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.4, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-02-27T20:21:38.760", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/seerr-team/seerr/commit/4ae20684092b5b28527b23dfbc1a3417858fee8e"}, {"source": "security-advisories@github.com", "url": "https://github.com/seerr-team/seerr/releases/tag/v3.1.0"}, {"source": "security-advisories@github.com", "url": "https://github.com/seerr-team/seerr/security/advisories/GHSA-rc4w-7m3r-c2f7"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-288"}, {"lang": "en", "value": "CWE-807"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{}