CVE-2018-25114: A remote code execution vulnerability exists within osCommerce Online Merchant version 2.3.4.1 due to insecure default configuration and missing authentication…

PriorityP182critical9.3CVSS 4.0

AVNACLATNPRNUINVCHVIHVAHSCNSINSANEXCRXIRXARXMAVXMACXMATXMPRXMUIXMVCXMVIXMVAXMSCXMSIXMSAXSXAUXRXVXREXUX

ITWEXPLOITVulnCheck KEV

Exploited in the wild

EPSS

2.82%

84.8th percentile

A remote code execution vulnerability exists within osCommerce Online Merchant version 2.3.4.1 due to insecure default configuration and missing authentication in the installer workflow. By default, the /install/ directory remains accessible after installation. An unauthenticated attacker can invoke install_4.php, submit crafted POST data, and inject arbitrary PHP code into the configure.php file. When the application later includes this file, the injected payload is executed, resulting in full server-side compromise.

Affected

1 ranges

Vendor	Product	Version range	Fixed in
oscommerce	online_merchant	—	—

Detection & IOCsextracted from sources · hover to see the quote

path/install/install.php?step=4↗

path/install/includes/configure.php↗

path/install/↗

commandDIR_FS_DOCUMENT_ROOT=.%2F&DB_DATABASE=%27%29%3Bpassthru%28%27cat+%2Fetc%2Fpasswd%27%29%3B%2F%2A↗

filenameinstall_4.php↗

→Detect exploitation attempts by monitoring POST requests to /install/install.php?step=4 with DB_DATABASE parameter containing PHP injection payloads (e.g., passthru, system, exec calls encoded in the POST body). ↗
→Alert on GET requests to /install/includes/configure.php after a POST to /install/install.php?step=4, as this two-step sequence indicates the attacker is triggering injected PHP code execution. ↗
→Monitor for the presence of an accessible /install/ directory post-installation; its existence is a prerequisite for exploitation. ↗
→Inspect POST body for URL-encoded PHP function calls (passthru, system, exec) within the DB_DATABASE field targeting /install/install.php. ↗

·The vulnerability is only exploitable if the /install/ directory remains accessible after installation; removing it fully mitigates the attack surface. ↗
·The Nuclei template uses a two-request sequence (POST to inject, GET to trigger); detection rules should correlate both requests from the same source IP within a short time window. ↗

CVSS provenance

nvdv4.09.3CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

vulncheck9.3CRITICAL

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