CVE-2026-4239 - Vulnerability Details

- Lagom WHMCS Template Datatables prototype pollution

Description

A vulnerability was found in Lagom WHMCS Template up to 2.3.7. Impacted is an unknown function of the component Datatables. The manipulation results in improperly controlled modification of object prototype attributes. It is possible to launch the attack remotely. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.

Published: 2026-03-16

Score: 5.1 Medium

EPSS: < 1% Very Low

KEV: No

Impact:

Action:

Analysis

Impact

A vulnerability was identified in the Lagom WHMCS Template version 2.3.7 and earlier, affecting the component that implements Datatables. By manipulating certain user inputs, an attacker can cause the application to alter JavaScript object prototype properties, a flaw known as prototype pollution. This vulnerability can be triggered remotely and an exploit is publicly available, enabling an adversary to potentially modify application logic or inject malicious data.

Affected Systems

The affected product is Lagom WHMCS Template and all releases up to version 2.3.7 are impacted. Any deployment of these versions that utilizes the Datatables portion of the template is at risk because the vulnerability resides in the Datatables handling code.

Risk and Exploitability

The CVSS score for the issue is 5.1, indicating medium severity. EPSS data is not available, and the vulnerability is not listed in CISA's KEV catalog. However, the public nature of the exploit and the remote attack vector increase the likelihood of real‑world exploitation. Organizations using the affected template should treat this as a moderate risk and act promptly to remediate.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Lagom

WHMCS Template

affected

Version	Status	Constraints
`2.3.0`	affected	—
`2.3.1`	affected	—
`2.3.2`	affected	—
`2.3.3`	affected	—
`2.3.4`	affected	—
`2.3.5`	affected	—
`2.3.6`	affected	—
`2.3.7`	affected	—

No data.

Vendor Product Confidence Versions

Lagom

Whmcs Template

100%

Version	Status	Scheme	Platform
`2.3.0`	affected	semver	—
`2.3.1`	affected	semver	—
`2.3.2`	affected	semver	—
`2.3.3`	affected	semver	—
`2.3.4`	affected	semver	—
`2.3.5`	affected	semver	—
`2.3.6`	affected	semver	—
`2.3.7`	affected	semver	—

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Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

Check Lagom's official website or repository for an updated WHMCS Template that fixes the prototype pollution issue.
If a newer version is available, upgrade your template installation to that version immediately.
If no update is released, disable or remove the Datatables component from the template to eliminate the vulnerable code path.
If disabling Datatables is not possible, add strict input sanitization or validation to restrict data that can affect prototype properties.
Monitor application logs and user activity for signs of exploitation and apply any additional hardening measures.

Generated by OpenCVE AI on March 17, 2026 at 12:07 UTC.

Tracking

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Advisories

No advisories yet.

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Attack Requirements None

User Interaction Passive

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact Low

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact Low

Availability Impact None

User Interaction Required

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact Low

Availability Impact None

User Interaction Required

Access Vector Network

Access Complexity Low

Authentication Single

Confidentiality Impact None

Integrity Impact Partial

Availability Impact None

This CVE is not in the KEV list.

The EPSS score is 0.00043.

Exploitation poc

Automatable no

Technical Impact partial

References

Link	Providers
https://github.com/devsamuelsantiago/lagom-prototype-pollution-poc/
https://github.com/devsamuelsantiago/lagom-prototype-pollution-poc/blob/main/lagom-prototype-pollution-poc.js
https://vuldb.com/?ctiid.351181
https://vuldb.com/?id.351181
https://vuldb.com/?submit.771350

History

Tue, 17 Mar 2026 10:00:00 +0000

Type	Values Removed	Values Added
First Time appeared		Lagom Lagom whmcs Template
Vendors & Products		Lagom Lagom whmcs Template

Mon, 16 Mar 2026 15:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Mon, 16 Mar 2026 13:45:00 +0000

Type	Values Removed	Values Added
Description		A vulnerability was found in Lagom WHMCS Template up to 2.3.7. Impacted is an unknown function of the component Datatables. The manipulation results in improperly controlled modification of object prototype attributes. It is possible to launch the attack remotely. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.
Title		Lagom WHMCS Template Datatables prototype pollution
Weaknesses		CWE-1321 CWE-94
References		https://github.com/devsamuelsantiago/lagom-prototype-pollution-poc/ https://github.com/devsamuelsantiago/lagom-prototype-pollution-poc/blob/main/lagom-prototype-pollution-poc.js https://vuldb.com/?ctiid.351181 https://vuldb.com/?id.351181 https://vuldb.com/?submit.771350
Metrics		cvssV2_0 `{'score': 4, 'vector': 'AV:N/AC:L/Au:S/C:N/I:P/A:N/E:POC/RL:ND/RC:UR'}` cvssV3_0 `{'score': 3.5, 'vector': 'CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R'}` cvssV3_1 `{'score': 3.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R'}` cvssV4_0 `{'score': 5.1, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P'}`

Subscriptions

Lagom Whmcs Template

MITRE

Status: PUBLISHED

Assigner: VulDB

Published: 2026-03-16T13:02:08.856Z

Updated: 2026-03-16T14:42:22.402Z

Reserved: 2026-03-15T20:37:03.899Z

Link: CVE-2026-4239

Vulnrichment

Updated: 2026-03-16T14:42:19.236Z

NVD

Status : Deferred

Published: 2026-03-16T14:20:18.703

Modified: 2026-04-29T01:00:01.613

Link: CVE-2026-4239

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-03-24T10:44:32Z

Weaknesses

Impact

Affected Systems

Risk and Exploitability

Tracking

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Attack Requirements None

User Interaction Passive

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact Low

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact Low

Availability Impact None

User Interaction Required

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact Low

Availability Impact None

User Interaction Required

Access Vector Network

Access Complexity Low

Authentication Single

Confidentiality Impact None

Integrity Impact Partial

Availability Impact None

Exploitation poc

Automatable no

Technical Impact partial

Subscriptions

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