Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessObtain valid low-privilege cPanel credentials
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DeliverySend crafted Park API request with eval-injection payload
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ExploitUnsanitized input reaches dynamic eval function
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ExecutionPayload executes as root within cPanel process
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ImpactFull server compromise achieved
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Eval input sanitization
MITRE ATT&CK
1 technique across 1 tactic: Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | Exploitation requires possession of a valid cPanel user account with at least low-privilege access - any legitimate tenant, reseller, or sub-account credential is sufficient. The vulnerable component is the Park API (domain parking functionality), which is a core, default-enabled cPanel feature; no non-standard configuration is required to expose the attack surface. The CVSS PR:L metric confirms that unauthenticated exploitation is not possible - the attacker must first obtain or compromise valid cPanel credentials. Physical or local server access is not required; exploitation is fully remote over the network. There is no user-interaction requirement. The primary limiting factor for exploitation at scale is the need for a valid credential, which in a shared hosting context may be obtained through phishing, credential stuffing, or purchasing access to compromised accounts. |
| Impact | The CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H) reflects a network-reachable, low-complexity attack requiring only a low-privilege authenticated session - consistent with any valid cPanel tenant or reseller account. The complete VC/VI/VA impact triad at High reflects full server compromise once exploitation succeeds. EPSS data is not provided in the input, and the vulnerability is not currently listed in the CISA KEV catalog, leaving real-world exploitation probability unconfirmed. The HackerOne disclosure origin suggests coordinated responsible disclosure with a vendor fix available, reducing (but not eliminating) immediate exploitation risk. The primary risk amplifier is cPanel's broad deployment across shared and managed hosting infrastructure: a single compromised low-privilege account could yield root access over an entire multi-tenant server, affecting every co-hosted site and their data. This is a genuine priority for any organization operating cPanel-based infrastructure. |
| Exploit ScenarioDerived | An attacker holding a valid low-privilege cPanel account - such as a shared hosting tenant - crafts a malicious request to the Park API endpoint, injecting code into a parameter that is processed by a dynamic evaluation function without sanitization. The injected payload executes within the cPanel process context, which operates as root, granting the attacker full control of the underlying server. From this position, the attacker can exfiltrate all hosted site data across every tenant, install persistent backdoors, or manipulate DNS and web service configuration. No public exploit code has been identified at time of analysis. |
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Alert meAnalysisAIv1 – Sep 01, 2026
Eval injection in cPanel's Park API (versions 11.138.0.0 and earlier) enables remote authenticated users to execute arbitrary code with root-level privileges on affected hosting servers. The vulnerability, classified under CWE-95 (Eval Injection) and reported via HackerOne, was disclosed alongside a WebPros vendor advisory on August 27, 2026. No public exploit code or CISA KEV listing has been identified at time of analysis, though the direct path to root execution across a widely deployed hosting platform makes this a critical remediation priority.
RemediationAI
Upgrade cPanel to a version above 11.138.0.0 per the vendor advisory at https://support.cpanel.net/hc/en-us/articles/42959571221527-Security-CVE-2026-65643-Park-API-Vulnerability-August-27-2026. The exact patched build number is not independently confirmed from available input data - consult the advisory directly for the precise target version before deploying. Administrators using cPanel's automatic update mechanism should verify that auto-updates are not suppressed in production environments, as this is the fastest remediation path. As a compensating control pending upgrade, consider disabling domain parking (addon/alias domain) functionality at the server level if it is not actively required - this removes the vulnerable API surface entirely, though it will prevent tenants from using domain parking features. Restricting Park API access to specific trusted reseller accounts is a narrower mitigation that limits exposure while preserving some functionality, at the cost of increased access-control management overhead.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
cPanel is a widely-used Linux-based web hosting control panel developed by WebPros (CPE: cpe:2.3:a:webpros:cpanel). The affected component is the Park API, which manages domain parking (alias domain) functionality. CWE-95 (Improper Neutralization of Directives in Dynamically Evaluated Code - 'Eval Injection') describes a condition where attacker-controlled input is passed to a dynamic code evaluation function - such as Perl's eval() or a similar construct - without adequate sanitization, causing the interpreter to execute attacker-supplied directives. Because cPanel's backend processes require elevated OS privileges to manage server configuration, web services, and DNS, successful injection results in code execution within the root context, completely bypassing the privilege boundary of the originating authenticated session.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Network-reachable with low complexity; any authenticated user triggers root execution, constituting a scope change (S:C) with full C/I/A impact.
Primary rating from Vendor (hackerone).
CVSS VectorVendor: hackerone
Lifecycle Timeline
2DescriptionCVE.org
Eval injection in cPanel 11.138.0.0 and earlier allows remote authenticated users to execute arbitrary code as root.
Executive ViewAI
cPanel versions 11.138.0.0 and earlier contain a critical eval injection vulnerability in the Park API enabling root-level code execution for authenticated users; no public exploit identified at time of analysis. For organizations using cPanel or hosting providers deploying it, this represents severe infrastructure risk requiring immediate containment of administrative access.
No vendor-released patch identified at time of analysis. Interim mitigations: (1) disable Park API if not required; (2) implement strict network segmentation for Park API endpoints; (3) enforce multi-factor authentication for administrative Park API access; (4) deploy intrusion detection systems monitoring API traffic for eval injection patterns; (5) maintain comprehensive audit logs of all Park API access.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Code injection occurs when an application accepts user input and passes it directly into a language interpreter or evaluator without proper sanitization.
Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.
Root-level remote code execution in WebPros cPanel is achievable by any mail-enabled account through a SQL injection fla
An issue was discovered in cPanel before 11.109.9999.116. Rated medium severity (CVSS 6.1), this vulnerability is remote
cPanel through 74 allows XSS via a crafted filename in the logs subdirectory of a user account, because the filename is
OS command injection in cPanel and WP Squared allows an authenticated, low-privileged hosting account holder to execute
OS command injection in the AUTOM8N plugin for WHM/cPanel (all versions through commit 82821f7) allows an attacker who c
cPanel before 88.0.13 mishandles file-extension dispatching, leading to code execution (SEC-488). Rated critical severit
In cPanel before 88.0.3, insecure chkservd test credentials are used on a templated VM (SEC-554). Rated critical severit
In cPanel before 88.0.3, insecure RNDC credentials are used for BIND on a templated VM (SEC-549). Rated critical severit
chsh in cPanel before 88.0.3 allows a Jailshell escape (SEC-497). Rated critical severity (CVSS 9.8), this vulnerability
cPanel before 88.0.3 mishandles the Exim filter path, leading to remote code execution (SEC-485). Rated critical severit
cPanel before 84.0.20 allows a demo account to achieve code execution via PassengerApps APIs (SEC-546). Rated critical s
cPanel before 84.0.20 allows a demo account to achieve remote code execution via a cpsrvd rsync shell (SEC-544). Rated c
EUVD-2026-68922
GHSA-3x5r-hcq6-ggfv
NVD
CVE.org
EPSS
Vulnrichment
VulDB
Exploit-DB