CVE-2023-4308

User Submitted Posts <= 20230809 - Unauthenticated Stored Cross-Site Scripting via 'user-submitted-content'

2023-08-14 00:00

Strategic Overview

Status: Patched in 20230811
Affected Plugin: User Submitted Posts – Enable Users to Submit Posts from the Front End
Affected Version: <= 20230809
CVSS: 7.2High
Weakness type: CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE: CVE-2023-4308

View all User Submitted Posts – Enable Users to Submit Posts from the Front End vulnerabilities

At a glance

CVE-2023-4308 is a high-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the User Submitted Posts WordPress plugin, affecting versions <= 20230809. It carries a CVSS score of 7.2 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 20230811; sites on affected versions should update now. Disclosed August 2023, reported by Ngô Thiên An (ancorn_).

Vulnerability Overview

The User Submitted Posts plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘user-submitted-content’ parameter in versions up to, and including, 20230809 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

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

User Submitted Posts <= 20230809 carries this weakness at user-submitted-content, and reaching it takes no account at all. 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 User Submitted Posts the fix is 20230811: builds <= 20230809 are affected, anything from 20230811 onward is not.

Remediation

Update to version 20230811, or a newer patched version

How does WordSec protect against this?

Requests carrying this pattern arrive without a session, so nothing upstream of the firewall gets a chance to reject them: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: User Submitted Posts 20230811 closes this, and updating the plugin is the step that ends it.

Firewall
Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2023-4308 https://www.wordfence.com/threat-intel/vulnerabilities/id/3bb4d37c-c4c2-4523-9b4e-73ffb7be81ea https://nvd.nist.gov/vuln/detail/CVE-2023-4308

Related records

Same weakness class

CVSS Vector

7.2

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

Base

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

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