Low severity · published Mar 16, 2026
CVE-2026-4239
Lagom WHMCS Template Datatables prototype pollution
3.5
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 12% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WT
WHMCS Template · Lagom
2.3.0; 2.3.1; 2.3.2; 2.3.3; 2.3.4; 2.3.5; +2 more · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-4239
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-4239
github.com
https://github.com/devsamuelsantiago/lagom-prototype-pollution-poc/
github.com
https://github.com/devsamuelsantiago/lagom-prototype-pollution-poc/blob/main/lagom-prototype-pollution-poc.js
vuldb.com
https://vuldb.com/?ctiid.351181
vuldb.com
https://vuldb.com/?id.351181
vuldb.com
https://vuldb.com/?submit.771350
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