CVE-2021-24975

NextScripts: Social Networks Auto-Poster <= 4.3.23 - Unauthenticated Stored Cross-Site Scripting

2022-01-03 00:00
Krzysztof Zając

Strategic Overview

Status
Patched in 4.3.24
Affected Plugin
NextScripts: Social Networks Auto-Poster
Affected Version
< 4.3.24
CVSS
6.1Medium
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE
CVE-2021-24975
View all NextScripts: Social Networks Auto-Poster vulnerabilities

At a glance

CVE-2021-24975 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the NextScripts WordPress plugin, affecting versions < 4.3.24. 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 4.3.24; sites on affected versions should update now. Disclosed January 2022, reported by Krzysztof Zając.

Vulnerability Overview

The NextScripts: Social Networks Auto-Poster WordPress plugin before 4.3.24 does not sanitise and escape logged requests before outputting them in the related admin dashboard, leading to an Unauthenticated Stored 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 NextScripts < 4.3.24 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 NextScripts the fix is 4.3.24: builds < 4.3.24 are affected, anything from 4.3.24 onward is not.

Remediation

Update to version 4.3.24, 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: NextScripts 4.3.24 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-2021-24975https://www.wordfence.com/threat-intel/vulnerabilities/id/0c0c1e62-1a1c-4a76-bd99-7ede232dc965https://nvd.nist.gov/vuln/detail/CVE-2021-24975

Related records

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