CVE-2026-43633

HestiaCP versions 1.9.0 through 1.9.4 contain a deserialization vulnerability in the web terminal component caused by a session format mismatch between PHP and Node.js that allows unauthenticated remote attackers to achieve root-level code execution. Attackers can inject crafted data into HTTP headers that are processed by the PHP session handler but incorrectly deserialized by the Node.js web terminal component as trusted session values, resulting in arbitrary command execution on systems with the web terminal feature enabled.

CVSS v3 10.0 CRITICAL

10.0^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/hestiacp/hestiacp/commit/854d71b3c1737b0a0d0cc55c926008ffe1f6719b
https://github.com/hestiacp/hestiacp/issues/5229
https://github.com/hestiacp/hestiacp/pull/5244
https://mercuryiss.com.au/hestiacp-unauthenticated-rce-ip-spoofing-cve-2026-43633-cve-2026-43634
https://www.vulncheck.com/advisories/hestiacp-deserialization-rce-via-web-terminal

Configurations

No configuration.

History

19 May 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-19 14:16

Updated : 2026-05-19 14:43

NVD link : CVE-2026-43633

Mitre link : CVE-2026-43633

CVE.ORG link : CVE-2026-43633

JSON object : View

Products Affected

No product.

CWE

CWE-502

Deserialization of Untrusted Data

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