CVE-2021-24932

Auto Featured Image <= 3.9.2 - Reflected Cross-Site Scripting

2021-11-15 00:00
ZhongFu Su

Strategic Overview

Status
Patched in 3.9.3
Affected Plugin
Auto Featured Image (Auto Post Thumbnail)
Affected Version
<= 3.9.2
CVSS
6.1Medium
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE
CVE-2021-24932
View all Auto Featured Image (Auto Post Thumbnail) vulnerabilities

At a glance

CVE-2021-24932 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Auto Featured Image (Auto Post Thumbnail) WordPress plugin, affecting versions <= 3.9.2. 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 3.9.3; sites on affected versions should update now. Disclosed November 2021, reported by ZhongFu Su.

Vulnerability Overview

The Auto Featured Image (Auto Post Thumbnail) WordPress plugin before 3.9.3 does not sanitise and escape the post_id parameter before outputting back in an admin page within a JS block, leading to a Reflected Cross-Site Scripting issue.

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')

Reaching this weakness in Auto Featured Image (Auto Post Thumbnail) <= 3.9.2 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 Auto Featured Image (Auto Post Thumbnail) the fix is 3.9.3: builds <= 3.9.2 are affected, anything from 3.9.3 onward is not.

Remediation

Update to version 3.9.3, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Auto Featured Image (Auto Post Thumbnail): WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Auto Featured Image (Auto Post Thumbnail) 3.9.3 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-24932https://www.wordfence.com/threat-intel/vulnerabilities/id/222325e9-3048-45f7-9a66-a713d096d44ehttps://nvd.nist.gov/vuln/detail/CVE-2021-24932

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C