Heimdall trusted the incoming X-Forwarded-Host header for URL generation, so
a spoofed value poisoned the page base href, asset() URLs and redirect
targets - loading assets from and redirecting to an attacker-controlled host
(CVE-2025-50578).
- TrustProxies no longer trusts X-Forwarded-Host; a forged value can no longer
influence getHost(), url(), asset() or redirects. X-Forwarded-For/Port/Proto
handling is unchanged.
- Trusted proxies are now configurable via the TRUSTED_PROXIES env var
(comma-separated CIDRs/IPs, "*" to trust all), defaulting to the previous
private ranges.
- Added an opt-in TRUSTED_HOSTS allow-list: when set, only the listed hosts are
served and any other Host header is rejected. Unset keeps the historic
behaviour of serving arbitrary hosts, so existing installs are unaffected.
Resolves#1451
KodeStar
Chris Hunt
Shift
Tobias Kolzer
KodeStar
Attila Kerekes
Kode