{"id":"CVE-2026-73291","aliases":["EUVD-2026-57237","GHSA-mc6w-69r3-62h8"],"status":"published","title":"Seerr: Path traversal to RCE via /avatarproxy image cache filename from upstream ETag","description":"Seerr is an open-source media request and discovery manager for Jellyfin, Plex, and Emby. Prior to version 3.4.0, Seerr's ImageProxy in server/lib/imageproxy.ts uses the upstream ETag and Content-Type response headers to build a cache filename for the unauthenticated GET /avatarproxy/:jellyfinUserId route, allowing a malicious or compromised Jellyfin or Emby server, or a man-in-the-middle attacker on a plaintext media-server connection, to supply traversal sequences that path.join and fs.writeFile normalize outside the cache directory, overwrite /app/dist/index.js or other files, and execute code as the node user after a container restart. This issue is fixed in version 3.4.0.","severity":{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00387,"percentile":0.33038,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-22","CWE-94"],"published":"2026-08-12T14:48:21Z","modified":"2026-10-28T02:30:59Z","products":[{"vendor":"seerr-team","product":"seerr"}],"references":[{"url":"https://github.com/seerr-team/seerr/security/advisories/GHSA-mc6w-69r3-62h8","tags":["x_refsource_CONFIRM","advisory"]},{"url":"https://github.com/seerr-team/seerr/commit/f484791105bd81bd5404e01410431ee6fe5769c2","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/seerr-team/seerr/releases/tag/v3.4.0","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/73xxx/CVE-2026-73291.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-73291","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-73291","title":"Seerr: Path traversal to RCE via /avatarproxy image cache filename from upstream ETag","description":"Seerr is an open-source media request and discovery manager for Jellyfin, Plex, and Emby. Prior to version 3.4.0, Seerr's ImageProxy in server/lib/imageproxy.ts uses the upstream ETag and Content-Type response headers to build a cache filename for the unauthenticated GET /avatarproxy/:jellyfinUserId route, allowing a malicious or compromised Jellyfin or Emby server, or a man-in-the-middle attacker on a plaintext media-server connection, to supply traversal sequences that path.join and fs.writeFile normalize outside the cache directory, overwrite /app/dist/index.js or other files, and execute code as the node user after a container restart. This issue is fixed in version 3.4.0.","status":"published","published":"2026-08-12T14:48:21.783Z","modified":"2026-08-13T16:23:07.044Z","cvss":[{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-22","CWE-94"],"updated_at":"2026-11-02T13:43:22.599321Z"}],"euvd":[{"id":"EUVD-2026-57237","description":"Seerr is an open-source media request and discovery manager for Jellyfin, Plex, and Emby. Prior to version 3.4.0, Seerr's ImageProxy in server/lib/imageproxy.ts uses the upstream ETag and Content-Type response headers to build a cache filename for the unauthenticated GET /avatarproxy/:jellyfinUserId route, allowing a malicious or compromised Jellyfin or Emby server, or a man-in-the-middle attacker on a plaintext media-server connection, to supply traversal sequences that path.join and fs.writeFile normalize outside the cache directory, overwrite /app/dist/index.js or other files, and execute code as the node user after a container restart. This issue is fixed in version 3.4.0.","status":"published","published":"2026-08-12T14:48:21Z","modified":"2026-08-13T16:23:07Z","cvss":[{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T18:01:55.61982Z"}],"nvd":[{"id":"CVE-2026-73291","description":"Seerr is an open-source media request and discovery manager for Jellyfin, Plex, and Emby. Prior to version 3.4.0, Seerr's ImageProxy in server/lib/imageproxy.ts uses the upstream ETag and Content-Type response headers to build a cache filename for the unauthenticated GET /avatarproxy/:jellyfinUserId route, allowing a malicious or compromised Jellyfin or Emby server, or a man-in-the-middle attacker on a plaintext media-server connection, to supply traversal sequences that path.join and fs.writeFile normalize outside the cache directory, overwrite /app/dist/index.js or other files, and execute code as the node user after a container restart. This issue is fixed in version 3.4.0.","status":"published","published":"2026-08-12T15:18:33.02Z","modified":"2026-10-24T15:10:00.19Z","cvss":[{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-22","CWE-94"],"updated_at":"2026-11-02T14:12:36.880938Z"}],"osv":[{"id":"CVE-2026-73291","title":"Seerr: Path traversal to RCE via /avatarproxy image cache filename from upstream ETag","description":"Seerr is an open-source media request and discovery manager for Jellyfin, Plex, and Emby. Prior to version 3.4.0, Seerr's ImageProxy in server/lib/imageproxy.ts uses the upstream ETag and Content-Type response headers to build a cache filename for the unauthenticated GET /avatarproxy/:jellyfinUserId route, allowing a malicious or compromised Jellyfin or Emby server, or a man-in-the-middle attacker on a plaintext media-server connection, to supply traversal sequences that path.join and fs.writeFile normalize outside the cache directory, overwrite /app/dist/index.js or other files, and execute code as the node user after a container restart. This issue is fixed in version 3.4.0.","status":"published","published":"2026-08-12T14:48:21.783Z","modified":"2026-10-28T02:30:59.731248579Z","cvss":[{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:H","level":"high"}],"cwes":["CWE-22","CWE-94"],"updated_at":"2026-11-02T15:45:16.365946Z"}]}}