Display Post Metadata <= 1.4.0 - Stored Cross-Site Scripting
Strategic Overview
- Status
- Patched in 1.5.0
- Affected Plugin
- Display Post Metadata
- Affected Version
< 1.5.0- CVSS
- 5.4Medium
- Weakness type
- CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
- CVE
CVE-2021-24855
At a glance
CVE-2021-24855 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Display Post Metadata WordPress plugin, affecting versions < 1.5.0. It carries a CVSS score of 5.4 (reachable over the network; low attack complexity). The issue is fixed in version 1.5.0; sites on affected versions should update now. Disclosed November 2021, reported by Francesco Carlucci.
Vulnerability Overview
The Display Post Metadata for WordPress is vulnerable to Stored Cross-Site Scripting via the 'custom_fields’ parameter in versions up to, and including, 1.4.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers as low as contributor level roles 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.
CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Display Post Metadata < 1.5.0 carries this weakness at custom_fields, 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 Display Post Metadata the fix is 1.5.0: builds < 1.5.0 are affected, anything from 1.5.0 onward is not.
Remediation
Update to version 1.5.0, or a newer patched version
How does WordSec protect against this?
The attempt arrives as an ordinary request to Display Post Metadata: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Display Post Metadata 1.5.0 closes this, and updating the plugin is the step that ends it.
- Firewall
- Alerts
External References
Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C