CVE-2021-26540

MediumCVSS 5.3/10Last modified Jun 17, 2026

Description

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".

Metrics

CVSS 3.1 5.3/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected software

No affected versions have been published.

Timeline

Published
Feb 8, 2021
Last modified
Jun 17, 2026
NVD status
Modified

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CVE-2021-26540: Medium severity, CVSS 5.3 | Vulnix