CVE-2021-26540
Last modified
CVE-2021-26540 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. 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".. EPSS estimates a 1.75% chance of exploitation in the next 30 days.
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/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Apostrophecms | Sanitize-Html | < 2.3.2 |
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
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
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