Open Redirect in Linuxserver Docker-Heimdall
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`. 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.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.028 (85.9th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 86th percentile — 85.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.028 · newest: 0.028 · change: +0.000
Affected products
- Linuxserver Docker-Heimdall — versions 2.6.3-ls307
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/linuxserver/Heimdall (Product)
- medium.com/@juanfelipeoz.rar/cve-2025-50578-exploiting-host-header-injection-op… (Exploit, Third Party Advisory)
- github.com/linuxserver/Heimdall/issues/1451 (Exploit, Issue Tracking)
Frequently asked questions
- What is CVE-2025-50578?
- CVE-2025-50578 is a critical-severity vulnerability in Linuxserver Docker-Heimdall, classified under Improper Input Validation. CVSS score: 9.8/10. Published 2025-07-30.
- How severe is CVE-2025-50578?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2025-50578 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.