CVEvulnerability
CVE-2021-26540
5.3 MEDIUM
Official page ↗
- Status
- Modified
- Published
- 2021-02-08
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 5.3 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- CVSS 2.0 ([email protected])
- 5.0 MEDIUM — AV:N/AC:L/Au:N/C:N/I:P/A:N
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".
Affected configurations
• apostrophecms sanitize-html (< 2.3.2)
References
- https://advisory.checkmarx.net/advisory/CX-2021-4309 Exploit, Patch, Third Party Advisory
- https://github.com/apostrophecms/sanitize-html/blob/main/CHANGELOG.md#232-2021-01-26 Release Notes, Third Party Advisory
- https://github.com/apostrophecms/sanitize-html/pull/460 Patch, Third Party Advisory
- https://advisory.checkmarx.net/advisory/CX-2021-4309 Exploit, Patch, Third Party Advisory
- https://github.com/apostrophecms/sanitize-html/blob/main/CHANGELOG.md#232-2021-01-26 Release Notes, Third Party Advisory
- https://github.com/apostrophecms/sanitize-html/pull/460 Patch, Third Party Advisory