CVE-2021-34641

SEOPress 5.0.0 - 5.0.3 - Stored Cross-Site Scripting

2021-08-16 15:33
Chloe Chamberland

Strategic Overview

Status
Patched in 5.0.4
Affected Plugin
SEOPress – AI SEO Plugin & On-site SEO
Affected Version
5.0.0 – 5.0.3 · 4 branches
CVSS
6.4Medium
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE
CVE-2021-34641
View all SEOPress – AI SEO Plugin & On-site SEO vulnerabilities

At a glance

CVE-2021-34641 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the SEOPress WordPress plugin, affecting versions 5.0.0 – 5.0.3 · 4 branches. It carries a CVSS score of 6.4 (reachable over the network; low attack complexity). The issue is fixed in version 5.0.4; sites on affected versions should update now. Disclosed August 2021, reported by Chloe Chamberland.

Vulnerability Overview

The SEOPress WordPress plugin is vulnerable to Stored Cross-Site-Scripting via the processPut function found in the ~/src/Actions/Api/TitleDescriptionMeta.php file which allows authenticated attackers to inject arbitrary web scripts, in versions 5.0.0 - 5.0.3.

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 interaction from a victim user.

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

Reaching this weakness in SEOPress 5.0.0 – 5.0.3 · 4 branches 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 SEOPress the fix is 5.0.4: builds 5.0.0 – 5.0.3 · 4 branches are affected, anything from 5.0.4 onward is not.

Remediation

Update to version 5.0.4, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to SEOPress: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: SEOPress 5.0.4 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-34641https://www.wordfence.com/threat-intel/vulnerabilities/id/9157fa5e-3af8-48ee-bb73-3df6109aae76https://nvd.nist.gov/vuln/detail/CVE-2021-34641

Related records

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