CVE-2021-26540
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…
Does this matter?
Lower severity and a low EPSS score (1.75%). Track it; it rarely justifies an emergency change on its own.
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".
- CVSS 3.1
- 5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- EPSS
- 1.75% probability · 77th percentile
- CISA KEV
- Not listed
- Affected
- apostrophecms/sanitize-html
- Source
- cve@mitre.org
References
- https://advisory.checkmarx.net/advisory/CX-2021-4309Exploit, Patch, Third Party Advisory
- https://github.com/apostrophecms/sanitize-html/blob/main/CHANGELOG.md#232-2021-01-26Release Notes, Third Party Advisory
- https://github.com/apostrophecms/sanitize-html/pull/460Patch, Third Party Advisory
- https://advisory.checkmarx.net/advisory/CX-2021-4309Exploit, Patch, Third Party Advisory
- https://github.com/apostrophecms/sanitize-html/blob/main/CHANGELOG.md#232-2021-01-26Release Notes, Third Party Advisory
- https://github.com/apostrophecms/sanitize-html/pull/460Patch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.