Medium

Improper Input Validation in sanitize-html

  • Disclosed: 06.05.2021
  • Updated: 11.10.2026 10:22

Apostrophe Technologies sanitize-html before 2.3.2 does not properly validate the hostnames set by the "allowedIframeHostnames" option when the "allowIframeRelativeUrls" is set to true, which allows attackers to bypass hostname whitelist for iframe element, related using an src value that starts with "/\example.com".

Affected software

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PlatformPackageVulnerable versionsFixed in
npm package sanitize-html < 2.3.2 2.3.2

References

CVSS score 5.3/10
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Weakness (CWE)
CWE-20
Platform
npm
Package
sanitize-html
Disclosed
06.05.2021
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-mjxr-4v3x-q3m4 - CC BY 4.0

Vulnerability history: sanitize-html

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

All (15) in the archive
Total entries
15
First → latest
11.2018 10.2026
Without a fix
0
Exploited in attacks
0

Severity breakdown

  • Critical 1
  • High 1
  • Medium 12
  • Low 1

Disclosures per year

  1. 2018: 2
  2. 2019: 0
  3. 2020: 1
  4. 2021: 2
  5. 2022: 1
  6. 2023: 0
  7. 2024: 1
  8. 2025: 1
  9. 2026: 7
Severity:
  1. Critical · 9.3 CVE-2026-44990 >= 2.17.3, < 2.17.4 2.17.4
  2. High · 7.5 CVE-2022-25887 < 2.7.1 2.7.1
  3. Improper Input Validation in sanitize-html this entry
    Medium · 5.3 CVE-2021-26540 < 2.3.2 2.3.2

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