CVE-2023-33999

Freemius SDK <= 2.5.9 - Reflected Cross-Site Scripting via fs_request_get

2023-07-18 00:00

Strategic Overview

Status: Patched in 11.3
Affected Plugin: WP TripAdvisor Review Slider
Affected Version: 10.4 – 11.2
CVSS: 6.1Medium
Weakness type: CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE: CVE-2023-33999

View all WP TripAdvisor Review Slider vulnerabilities

At a glance

CVE-2023-33999 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the WP TripAdvisor Review Slider WordPress plugin, affecting versions 10.4 – 11.2. It carries a CVSS score of 6.1 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 11.3; sites on affected versions should update now. Disclosed July 2023, reported by Rafie Muhammad.

Vulnerability Overview

The Freemius SDK for WordPress is vulnerable to Reflected Cross-Site Scripting via the ‘fs_request_get’ function in versions up to, and including, 2.5.9 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.

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.

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

WP TripAdvisor Review Slider 10.4 – 11.2 carries this weakness at fs_request_get, and reaching it takes a caller who can reach the endpoint. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.

Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For WP TripAdvisor Review Slider the fix is 11.3: builds 10.4 – 11.2 are affected, anything from 11.3 onward is not.

Remediation

Update to version 11.3, or a newer patched version

How WordSec helps

The attempt arrives as an ordinary request to WP TripAdvisor Review Slider: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: WP TripAdvisor Review Slider 11.3 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2023-33999 https://www.wordfence.com/threat-intel/vulnerabilities/id/5253fe2b-040b-417c-b257-0cb59ee5aa6e https://nvd.nist.gov/vuln/detail/CVE-2023-33999

Related records

Same weakness class

CVSS Vector

6.1

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionRequired
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityNone

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