CVE-2025-50578
LinuxServer.io heimdall 2.6.3-ls307 contains a vulnerability in how it handles user-supplied HTTP headers, specifically `X-Forwarded-Host` and `Referer`.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (2.97%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
LinuxServer.io heimdall 2.6.3-ls307 contains a vulnerability in how it handles user-supplied HTTP headers, specifically `X-Forwarded-Host` and `Referer`. An unauthenticated remote attacker can manipulate these headers to perform Host Header Injection and Open Redirect attacks. This allows the loading of external resources from attacker-controlled domains and unintended redirection of users, potentially enabling phishing, UI redress, and session theft. The vulnerability exists due to insufficient validation and trust of untrusted input, affecting the integrity and trustworthiness of the application.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 2.97% probability · 87th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-20, CWE-74, CWE-601
- Affected
- linuxserver/docker-heimdall
- Source
- cve@mitre.org
EPSS 3.0% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/linuxserver/HeimdallProduct
- https://github.com/linuxserver/Heimdall/issues/1451Exploit, Issue Tracking
- https://medium.com/@juanfelipeoz.rar/cve-2025-50578-exploiting-host-header-injection-open-redirect-in-heimdall-application-733afceff2eaExploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.