CVE-2025-50578
9.8
CRITICAL · CVSS 3.1 · EPSS 2.8% (pctl 86)
In your normal cycle
Critical by CVSS (9.8), but no sign of active exploitation.
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.
Scoring
| CVSS | 9.8 (CRITICAL, v3.1) |
|---|---|
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 2.8% — more likely to be exploited than 86% of all CVEs |
| Weakness | CWE-20 |
| On CISA KEV | no |
| Public exploit | none known |
| Published | 2025-07-30 |
| Last modified | 2026-06-17 |
Affected (1)
| Vendor | Product |
|---|---|
| linuxserver | docker-heimdall |
References
→ the Explorer · watch your stack · NVD