CVE-2021-21418Network attack vector

Stored XSS via unescaped newsletter conditions

Published Mar 31, 2021 · Updated Aug 3, 2024

Stored XSS in PrestaShop Email Subscription before 2.6.1 allows remote authenticated users to execute JavaScript in storefront users' browsers. The module reads NW_CONDITIONS and renders the value with Smarty's nofilter modifier in three front-office templates instead of HTML-encoding it. An employee-level back-office account must save a crafted condition, and a storefront visitor must load a newsletter form; the script then runs in that visitor's browser.

CVSS severity5.4
Medium
EPSS probability0.79%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Stored XSS in PrestaShop Email Subscription before 2.6.1 allows remote authenticated users to execute JavaScript in storefront users' browsers. The module reads NW_CONDITIONS and renders the value with Smarty's nofilter modifier in three front-office templates instead of HTML-encoding it. An employee-level back-office account must save a crafted condition, and a storefront visitor must load a newsletter form; the script then runs in that visitor's browser.

The record

CVE
CVE-2021-21418
Published
Mar 31, 2021
Updated
Aug 3, 2024
Vendor
PrestaShop
Product
Email Subscription
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 31, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 2.6.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

PrestaShop · Email Subscriptionversion=< 2.6.1

Published CVSS scores

4.6GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
3.5NIST NVDAV:N/AC:M/Au:S/C:N/I:P/A:N
5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007Command and Scripting Interpreter: JavaScript/JScript

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo