CVE-2020-35598: ACS Advanced Comment System 1.0 is affected by Directory Traversal via an advanced_component_system/index.php?ACS_path=..%2f URI. NOTE: this might be the same…

PriorityP262high7.5CVSS 3.1

AVNACLPRNUINSUCHINAN

EXPLOIT

EPSS

21.00%

97.3th percentile

ACS Advanced Comment System 1.0 is affected by Directory Traversal via an advanced_component_system/index.php?ACS_path=..%2f URI. NOTE: this might be the same as CVE-2009-4623

Affected

2 ranges

Vendor	Product	Version range	Fixed in
advanced_comment_system_project	advanced_comment_system	—	—
plohni	advanced_comment_system	—	—

Detection & IOCsextracted from sources · hover to see the quote

url/advanced_component_system/index.php?ACS_path=..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2fetc%2fpasswd%00↗

path/advanced_component_system/index.php↗

→Look for GET requests to /advanced_component_system/index.php with the ACS_path parameter containing URL-encoded path traversal sequences (..%2f) and a null byte (%00) terminator targeting /etc/passwd. ↗
→A successful exploitation response will return HTTP 200 and contain the string matching 'root:.*:0:0:' in the body, indicating /etc/passwd was read. ↗
→The vulnerability is triggered via the ACS_path GET parameter; monitor web logs for any requests to this endpoint containing '%2f' (URL-encoded slash) sequences indicative of directory traversal. ↗

·The exploit uses a null byte (%00) to terminate the path string, which is a technique that may only work on PHP versions where null byte injection in file paths is effective (typically PHP < 5.3.4). ↗
·This CVE may overlap with CVE-2009-4623, suggesting the vulnerability has been known for over a decade and affects the same codebase. ↗

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:P/I:N/A:N

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