Vulnerability · Published Aug 12, 2026 · Assigned by GitHub_M

CVE-2026-73291Seerr: Path traversal to RCE via /avatarproxy image cache filename from upstream ETag

High 7.1

In plain English

A high-severity path traversal in seerr from seerr-team. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 33% of all known vulnerabilities).

Severity (CVSS 3.1)7.1High

Exploit odds (30 days)0.4%top 67.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

Vendor	Product	Versions
seerr-team	seerr	< 3.4.0

Weakness: CWE-22, CWE-94 · Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:H

References

https://github.com/seerr-team/seerr/security/advisories/GHSA-mc6w-69r3-62h8 x_refsource_CONFIRM
https://github.com/seerr-team/seerr/commit/f484791105bd81bd5404e01410431ee6fe5769c2 x_refsource_MISC
https://github.com/seerr-team/seerr/releases/tag/v3.4.0 x_refsource_MISC