Medium

Cross-Site Scripting in i18next

  • Disclosed: 24.07.2018
  • Updated: 11.10.2026 10:22

Affected versions of i18next may fail to sanitize user input when certain configuration options are used. When using the .init method, passing interpolation options without passing an escapeValue will default to undefined rather than the assumed true.

Proof of Concept

js
var init = i18n.init({
  interpolation: {
    prefix: "__",
    suffix: "__",
    escapeValue: true
  }
}, function(){
  var test = i18n.t('__firstName__ __lastName__', {
        firstName: 'Bob',
        lastName: '["foo","bar"]',
  });
  console.log(test);
});

When escapeValue is explicitly passed, the result of test is:

html
<script>alert(1)</script> Johnson

This is supposed to be the default. However, if escapeValue is not included, the result is the unescaped string:

html
<script>alert(1)</script> Johnson

Recommendation

Update to version 3.4.4 or later.

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
npm package i18next >= 2.0.0, < 3.4.4 3.4.4

References

CVSS score 6.1/10
CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weakness (CWE)
CWE-79
Platform
npm
Package
i18next
Disclosed
24.07.2018
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-cmh5-qc8w-xvcq - CC BY 4.0

Vulnerability history: i18next

All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.

Total entries
2
First → latest
07.2018 11.2018
Without a fix
0
Exploited in attacks
0

Severity breakdown

  • Medium 2

Disclosures per year

  1. 2018: 2
  2. 2019: 0
  3. 2020: 0
  4. 2021: 0
  5. 2022: 0
  6. 2023: 0
  7. 2024: 0
  8. 2025: 0
  9. 2026: 0
  1. Medium · 6.1 CVE-2017-16008 < 1.10.3 1.10.3
  2. Cross-Site Scripting in i18next this entry
    Medium · 6.1 CVE-2017-16010 >= 2.0.0, < 3.4.4 3.4.4

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