CyberSecBulletin
CVE-2026-128041NVD status: Deferred

magento-lts: Improper Neutralization of Input During Web Page Generation

Published Updated By the CyberSecBulletin desk

CVE-2026-128041 is a high-severity improper neutralization of input during web page generation vulnerability in magento-lts from OpenMage, with a CVSS 3.1 base score of 8.0 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists versions 20.18.2, 21.0.0-beta3 as the first without the flaw, so updating magento-lts to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.3% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update magento-lts to 20.18.2 or 21.0.0-beta3, whichever matches your release line, or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  4. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
OpenMagemagento-ltsbefore 20.18.2; 21.0.0-beta1 up to, but not including, 21.0.0-beta320.18.2, 21.0.0-beta3

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
HighSuccess depends on conditions outside the attacker's control.
Privileges required
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

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

Scoring systemScoreSeverityScored by
CVSS 4.08.8HighCNA (vulncheck.com)
CVSS 3.18.0HighCNA (vulncheck.com)

Official description

OpenMage magento-lts before 20.18.2 and 21.0.0-beta1 before 21.0.0-beta3 serves RSS feeds with a text/html content type and does not escape feed entry data, leading to stored cross-site scripting. An unauthenticated guest can submit a product review with script in the nickname, title or text that executes when an administrator opens the pending-reviews feed, enabling admin account takeover.

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

Other vulnerabilities in magento-lts

All magento-lts vulnerabilities

Recent Improper Neutralization of Input During Web Page Generation vulnerabilities

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