Vulnerability in Opencart

CVE-2026-18412

OpenCart extensions are uploaded as zip files with .ocmod.zip extensions. Upon installation, the OpenCart v4.2.0.0 extension installer extracts these zip files, but does not validate that the extracted paths stay inside the intended extraction directory. An attacker can craft a malicious extension containing file path traversal sequences, such as ../. With this vulnerability, an attacker can write files, such as a PHP web shell, into the webroot directory.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.004 (37.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 38th percentile — 37.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-18412: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

References

Frequently asked questions

What is CVE-2026-18412?
CVE-2026-18412 is a critical-severity vulnerability in Opencart, classified under CWE-22: IMPROPER LIMITATION OF A PATHNAME TO A RESTRICTED DIRECTORY ('PATH TRAVERSAL'). CVSS score: 9.1/10. Published 2026-08-10.
How severe is CVE-2026-18412?
Critical severity. CVSS v3 base score is 9.1 out of 10.