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CVE-2026-120687NVD status: Deferred

Lightbox & Modal Popup WordPress Plugin – FooBox: Improper Neutralization of Input During Web Page Generation

CVE-2026-120687 is a high-severity improper neutralization of input during web page generation vulnerability in Lightbox & Modal Popup WordPress Plugin – FooBox from FooPlugins, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Lightbox & Modal Popup WordPress Plugin – FooBox versions: 2.8.7 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far, and no EPSS exploitation forecast has been published yet.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Lightbox & Modal Popup WordPress Plugin – FooBox you run against the affected versions below, and install the vendor's latest release.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
FoopluginsLightbox & Modal Popup WordPress Plugin – FooBox2.8.7 and earlierNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
LowSome restricted data can be read.
Integrity
LowLimited modification of data is possible.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N. Scored by CNA (wordfence.com).

Official description

The Lightbox & Modal Popup WordPress Plugin – FooBox plugin for WordPress is vulnerable to Stored DOM-Based Cross-Site Scripting via the 'img alt attribute inside .wp-caption container' parameter in all versions up to, and including, 2.8.7 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This is exploitable by Subscriber-level users when bbPress is installed, as its bbp_filter_kses filter chain permits img and pre tags while preserving numeric character references inside attribute values, allowing encoded payloads to bypass save-time sanitization and reach the vulnerable sink fully intact. Exploitation by attackers with subscriber-level access and above requires that bbPress 2.6.20 is installed, a public forum exists, and either the first topic has already been approved or subsequent topics clear moderation. On a default installation, where that is not configured, the vulnerability requires attackers with contributor-level access and above.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Neutralization of Input During Web Page Generation

The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

How developers prevent this class of flaw

  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples of libraries and frameworks that make it easier to generate properly encoded output include Microsoft's Anti-XSS library, the OWASP ESAPI Encoding module, and Apache Wicket.
  • Understand all the potential areas where untrusted inputs can enter your software: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.
  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

More Improper Neutralization of Input During Web Page Generation vulnerabilities (CWE-79)

Timeline

  1. CVE record published.

References

Recent Improper Neutralization of Input During Web Page Generation vulnerabilities

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