CVE-2026-43634
7.5 HIGHHestiaCP versions 1.2.0 through 1.9.4 contain an IP spoofing vulnerability that allows unauthenticated remote attackers to bypass authent...
Published: 2026-05-19 · Last updated: 2026-05-19
Severity and scoring
- CVSS
- 7.5 HIGH
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- CWE
- CWE-348
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.
Source: NVD
References
- [NVD]https://nvd.nist.gov/vuln/detail/CVE-2026-43634
- [Other]https://github.com/hestiacp/hestiacp/commit/f381e294500f671cf12716c638afd0bfde901f88
- [Other]https://github.com/hestiacp/hestiacp/issues/5229
- [Other]https://github.com/hestiacp/hestiacp/pull/5273
- [Other]https://mercuryiss.com.au/hestiacp-unauthenticated-rce-ip-spoofing-cve-2026-43633-cve-2026-43634
- [Other]https://www.vulncheck.com/advisories/hestiacp-ip-spoofing-via-cf-connecting-ip-header
Related CVEs
Same CWE
- CVE-2020-37248 — OfflineIMAP before 8.0.3 trusts the server with their STARTTLS capability prior to authentication, which allows STRIPTLS/man-in-the-middl... (6.5 MEDIUM)