Medium severity · published Jun 12, 2026
CVE-2026-53606
sanitize-html has an incomplete URI scheme validation that allows javascript: URIs through action, formaction, data, poster, and background attributes
5.4
CVSS
0.2%
EPSS
No
On KEV
Description
ApostropheCMS is an open-source Node.js content management system, and sanitize-html provides a simple HTML sanitizer with a clear API. Versions of sanitize-html prior to 2.17.5 use `allowedSchemesAppliedToAttributes` (default: `['href', 'src', 'cite']`) to gate the `naughtyHref()` function that blocks dangerous URI schemes like `javascript:` and `vbscript:`. The HTML specification defines 10+ attributes that accept URIs (`action`, `formaction`, `data`, `poster`, `background`, `ping`, `xlink:href`, `dynsrc`, `lowsrc`), but none of these are included in the default gate list. When a developer allows any of these attributes in their configuration, `javascript:` URIs pass through completely unmodified, enabling XSS. Version 2.17.5 patches the issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 11% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SA
sanitize-html · apostrophecms
< 2.17.5 · source: vendor
Affected product
SA
sanitize-html
apostrophecms
More from sanitize-html
9.3
CVE-2026-44990
Apostrophe has default XSS via `xmp` raw-text passthrough in `sanitize-html`
7.5
CVE-2022-25887
The package sanitize-html before 2.7.1 are vulnerable to Regular Expression Denial of Service (ReDoS) due to insecure global regular expression replacement logic of HTML comment…
6.1
CVE-2026-40186
ApostropheCMS: sanitize-html allowedTags Bypass via Entity-Decoded Text in nonTextTags Elements
6.1
CVE-2014-125128
'sanitize-html' prior to version 1.0.3 is vulnerable to Cross-site Scripting (XSS)
6.1
CVE-2019-25225
`sanitize-html` prior to version 2.0.0-beta is vulnerable to Cross-site Scripting (XSS)