Vulnerability · Published Feb 8, 2021 · Assigned by mitre
CVE-2021-26540
Medium 5.3
In plain English
A medium-severity security flaw in the sanitize-html package (npm). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.8% (higher than 78% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)5.3Medium
Exploit odds (30 days)1.8%top 21.7% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official 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 packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | sanitize-html | 2.3.2 | GHSA-mjxr-4v3x-q3m4 |
Affected products (as reported)
References
- https://github.com/apostrophecms/sanitize-html/blob/main/CHANGELOG.md#232-2021-01-26 x_refsource_MISC
- https://github.com/apostrophecms/sanitize-html/pull/460 x_refsource_MISC
- https://advisory.checkmarx.net/advisory/CX-2021-4309 x_refsource_MISC