Post Snippets <= 4.0.2 - Authenticated (Administrator+) Stored Cross-Site Scripting via 'snippet_content'
Strategic Overview
- Status
- Patched in 4.0.3
- Affected Plugin
- Post Snippets – Custom WordPress Code Snippets Customizer
- Affected Version
<= 4.0.2- CVSS
- 4.4Medium
- Weakness type
- CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
- CVE
CVE-2023-25459
At a glance
CVE-2023-25459 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Post Snippets WordPress plugin, affecting versions <= 4.0.2. It carries a CVSS score of 4.4 (reachable over the network). Exploitation requires an authenticated account at Administrator level or above. The issue is fixed in version 4.0.3; sites on affected versions should update now. Disclosed May 2023, reported by Abdi Pranata.
Vulnerability Overview
The Post Snippets plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘snippet_content’ parameter in versions up to, and including, 4.0.2 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only impacts multi-site installations and installations where unfiltered_html has been disabled.
Technical Analysis
The vector marks this flaw as remotely reachable over the network, and no interaction from a victim user.
CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Post Snippets <= 4.0.2 carries this weakness at snippet_content, and reaching it takes an account at Administrator level or above. 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 Post Snippets the fix is 4.0.3: builds <= 4.0.2 are affected, anything from 4.0.3 onward is not.
Remediation
Update to version 4.0.3, or a newer patched version
How does WordSec protect against this?
An attacker needs Administrator access first, so the firewall sees the attempt as traffic from a logged-in account: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Post Snippets 4.0.3 closes this, and updating the plugin is the step that ends it.
- Firewall
- Alerts
External References
Related records
Same weakness class
Other vulnerabilities in Post Snippets – Custom WordPress Code Snippets Customizer
- 9.6CVE-2021-25010: Post Snippets CSRF to Stored Cross-Site Scripting
CVE-2021-25010 - 8.8CVE-2026-56049: Post Snippets RCE
CVE-2026-56049 - 8.8CVE-2026-25001: Post Snippets RCE
CVE-2026-25001 - 8.8Freemius SDK <= 2.2.3 Arbitrary Options Update
- 6.3CVE-2022-4974: Freemius SDK <= 2.4.2 Missing Authorization Checks
CVE-2022-4974 - 4.3CVE-2025-63040: Post Snippets <= 4.0.11 Cross-Site Request Forgery
CVE-2025-63040
Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C