HestiaCP up to 1.9.4 less trusted source

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in HestiaCP up to 1.9.4. Impacted is an unknown function. Such manipulation leads to less trusted source. This vulnerability is listed as CVE-2026-43634. The attack may be performed from remote. There is no available exploit. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability was found in HestiaCP up to 1.9.4. It has been rated as problematic. Affected by this issue is some unknown functionality. The manipulation with an unknown input leads to a less trusted source vulnerability. Using CWE to declare the problem leads to CWE-348. The product has two different sources of the same data or information, but it uses the source that has less support for verification, is less trusted, or is less resistant to attack. Impacted is integrity. CVE summarizes:

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.

The weakness was presented by sutol. The advisory is shared for download at mercuryiss.com.au. This vulnerability is handled as CVE-2026-43634 since 05/01/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available.

Applying the patch f381e294500f671cf12716c638afd0bfde901f88 is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-30935). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Less trusted source
CWE: CWE-348
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: f381e294500f671cf12716c638afd0bfde901f88

Timelineinfo

05/01/2026 CVE reserved
05/19/2026 +18 days Advisory disclosed
05/19/2026 +0 days VulDB entry created
05/19/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: mercuryiss.com.au
Researcher: sutol
Status: Confirmed

CVE: CVE-2026-43634 (🔒)
GCVE (CVE): GCVE-0-2026-43634
GCVE (VulDB): GCVE-100-364688
EUVD: 🔒

Entryinfo

Created: 05/19/2026 17:16
Updated: 05/19/2026 17:59
Changes: 05/19/2026 17:16 (74), 05/19/2026 17:59 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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