CVE-2025-66508: 1Panel IP Access Control Bypass via Untrusted X-Forwarded-For Headers
Summary The server trusts all reverse-proxy headers by default, so any remote client can spoof X-Forwarded-For to bypass IP-based protections (AllowIPs, API IP whitelist, “localhost-only” checks). All IP-based access control becomes ineffective.
Details - Gin is created with defaults (gin.Default()), which sets TrustedProxies = 0.0.0.0/0 and uses X-Forwarded-For/X-Real-IP to compute ClientIP().
- IP-based controls rely on ClientIP(): - AllowIPs / BindDomain (core/middleware/iplimit.go, core/utils/security/security.go). - API IP whitelist (core/middleware/apiauth.go). - "localhost-only" checks that depend on ClientIP().
- Because no trusted-proxy range is enforced, any client can send X-Forwarded-For: 127.0.0.1 (or a whitelisted IP) and be treated as coming from that address.
Impact All IP-based access control is rendered ineffective: remote clients can masquerade as localhost or any whitelisted IP, defeating AllowIPs, API IP whitelists, and “localhost-only” protections.
Other sources
1Panel is an open-source, web-based control panel for Linux server management. Versions 2.0.14 and below use Gin's default configuration which trusts all IP addresses as proxies (TrustedProxies = 0.0.0.0/0), allowing any client to spoof the X-Forwarded-For header. Since all IP-based access controls (AllowIPs, API whitelists, localhost-only checks) rely on ClientIP(), attackers can bypass these protections by simply sending X-Forwarded-For: 127.0.0.1 or any whitelisted IP. This renders all IP-based security controls ineffective. This issue is fixed in version 2.0.14.
— MITRE
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2025-66508?
CVE-2025-66508 has been classified as a critical vulnerability due to its potential to bypass IP-based access controls.
How do I fix CVE-2025-66508?
To fix CVE-2025-66508, you should upgrade to version 0.0.0-20251201063338-94f7d78cc976 for the agent package or to 2.0.14 for the main package.
What are the risks associated with CVE-2025-66508?
The risks with CVE-2025-66508 include unauthorized access and potential exploitation of sensitive resources due to leaked IP information.
Which software versions are affected by CVE-2025-66508?
CVE-2025-66508 affects versions prior to 0.0.0-20251201063338-94f7d78cc976 for the agent package and earlier than 2.0.14 for the main package.
What does CVE-2025-66508 exploit?
CVE-2025-66508 exploits the trust in reverse-proxy headers, allowing attackers to spoof IP addresses and bypass access controls.