CVE-2026-43634 (GCVE-0-2026-43634)
Vulnerability from cvelistv5
Published
2026-05-19 13:33
Modified
2026-07-14 20:01
Severity ?
8.7 (High) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CWE
  • CWE-348 - Use of Less Trusted Source
Summary
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.
References
Impacted products
Vendor Product Version
hestiacp hestiacp Version: 1.2.0   ≤ 1.9.4
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