VULNERABILITY INTELLIGENCE
CVE-2026-43634
CVSS score8.7 HIGH
EPSS probability0.24%
CISA KEVNot currently listed
Published2026-05-19
Last modified2026-07-24
CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
Description
HestiaCP versions 1.2.0 through 1.9.4 contain an IP spoofing vulnerability that allows unauthenticated remote attackers to bypass authentication security controls by supplying an arbitrary IP address in the CF-Connecting-IP HTTP header without verifying the request originated from Cloudflare's network. Attackers can exploit this to circumvent fail2ban brute-force protection, bypass per-user IP allowlists, and poison authentication audit logs by spoofing trusted IP addresses on each request.
Weakness classification
- CWE-348: Use of Less Trusted Source