Description
Mega-Fence (webgate-lib.*) 25.1.914 and prior trusts the first value of the X-Forwarded-For (XFF) header as the client IP without validating a trusted proxy chain. An attacker can supply an arbitrary XFF value in a remote request to spoof the client IP, which is then propagated to security-relevant state (e.g., WG_CLIENT_IP cookie). Deployments that rely on this value for IP allowlists may be bypassed.
Metrics
CVSS 3.1 6.5/10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NWeakness enumeration
Affected software
No affected versions have been published.
Timeline
- Published
- Jan 5, 2026
- Last modified
- Jun 17, 2026
- NVD status
- Analyzed