CVE-2020-12832

Simple File List <= 4.2.7 - Arbitrary File Deletion

2020-05-16 00:00

Strategic Overview

Status: Patched in 4.2.8
Affected Plugin: Simple File List
Affected Version: <= 4.2.7
CVSS: 6.5Medium
Weakness type: CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CVE: CVE-2020-12832

View all Simple File List vulnerabilities

At a glance

CVE-2020-12832 is a medium-severity Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in the Simple File List WordPress plugin, affecting versions <= 4.2.7. It carries a CVSS score of 6.5 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 4.2.8; sites on affected versions should update now. Disclosed May 2020, reported by Christian Angel.

Vulnerability Overview

WordPress Plugin Simple File List before 4.2.8 is prone to a vulnerability that lets attackers delete arbitrary files because the application fails to properly verify user-supplied input.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Reaching this weakness in Simple File List <= 4.2.7 takes a caller who can reach the endpoint. Path traversal happens when user-controlled text is used to build a filesystem path without being constrained to an intended directory, so sequences like ../ walk the resolved path somewhere else.

Depending on the operation, it means reading files outside the intended folder — wp-config.php being the usual target — or writing to and deleting paths the web server can touch. For Simple File List the fix is 4.2.8: builds <= 4.2.7 are affected, anything from 4.2.8 onward is not.

Remediation

Update to version 4.2.8, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Simple File List: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Simple File List 4.2.8 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2020-12832 https://www.wordfence.com/threat-intel/vulnerabilities/id/b2d26156-b88c-4cae-a830-be765e1f1473 https://nvd.nist.gov/vuln/detail/CVE-2020-12832

Related records

Same weakness class

Other vulnerabilities in Simple File List

CVSS Vector

6.5

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityNone
IntegrityLow
AvailabilityLow

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