CVE-2024-4439

WordPress Core < 6.5.2 - Unauthenticated & Authenticated (Contributor+) Stored Cross-Site Scripting via Avatar Block

2024-04-09 00:00

Strategic Overview

Status: Patched in 6.0.8
Affected Core: WordPress 6.5
Affected Version: 6.0 – 6.5.1 · 6 branches
CVSS: 7.2High
Weakness type: CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE: CVE-2024-4439

At a glance

CVE-2024-4439 is a high-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the WordPress 6.5 WordPress release line, affecting 6.0 – 6.5.1 · 6 branches. It carries a CVSS score of 7.2 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 6.0.8; sites on affected versions should update now. Disclosed April 2024, reported by John Blackbourn.

Vulnerability Overview

WordPress Core is vulnerable to Stored Cross-Site Scripting via user display names in the Avatar block in various versions up to 6.5.2 due to insufficient output escaping on the display name. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. In addition, it also makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that have the comment block present and display the comment author's avatar.

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, and no interaction from a victim user.

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

Reaching this weakness in WordPress 6.5 6.0 – 6.5.1 · 6 branches 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 WordPress 6.5 the fix is 6.0.8: builds 6.0 – 6.5.1 · 6 branches are affected, anything from 6.0.8 onward is not.

Remediation

Update to one of the following versions, or a newer patched version: 6.0.8, 6.1.6, 6.2.5, 6.3.4, 6.4.4, 6.5.2

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: updating to 6.0.8 is the step that ends it.

Firewall
Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2024-4439 https://www.wordfence.com/threat-intel/vulnerabilities/id/e363c09a-4381-4b3a-951c-9a0ff5669016 https://nvd.nist.gov/vuln/detail/CVE-2024-4439

Related records

Same weakness class

Other vulnerabilities in WordPress 6.5

CVSS Vector

7.2

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

Base

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

This record contains material that is subject to copyright

CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE®). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.

https://www.cve.org/Legal/TermsOfUse

Defiant hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute this software vulnerability information. Any copy of the software vulnerability information you make for such purposes is authorized provided that you include a hyperlink to this vulnerability record and reproduce Defiant's copyright designation and this license in any such copy.

https://www.wordfence.com/wordfence-intelligence-terms-and-conditions/