CVE-2021-24953

Advanced iFrame <= 2021.9 Reflected Cross-Site Scripting

2022-02-02 00:00

Strategic Overview

Status: Patched in 2022
Affected Plugin: Advanced iFrame
Affected Version: <= 2021.9
CVSS: 6.1Medium
Weakness type: CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE: CVE-2021-24953

View all Advanced iFrame vulnerabilities

At a glance

CVE-2021-24953 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Advanced iFrame WordPress plugin, affecting versions <= 2021.9. 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 2022; sites on affected versions should update now. Disclosed February 2022, reported by ZhongFu Su.

Vulnerability Overview

The Advanced iFrame WordPress plugin before 2022 does not sanitise and escape the ai_config_id parameter before outputting it back in an admin page, 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 Advanced iFrame <= 2021.9 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 Advanced iFrame the fix is 2022: builds <= 2021.9 are affected, anything from 2022 onward is not.

Remediation

Update to version 2022, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Advanced iFrame: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Advanced iFrame 2022 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-24953 https://www.wordfence.com/threat-intel/vulnerabilities/id/b72dcc68-df81-47ac-bd73-6aee87611b90 https://nvd.nist.gov/vuln/detail/CVE-2021-24953

Related records

Same weakness class

Other vulnerabilities in Advanced iFrame

CVSS Vector

6.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionRequired
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityNone

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