CVE-2026-61784 Details
Description
xhtml-purifier is a Node.js library to take in raw/unknown/untrusted HTML and output cleaned, purified, trusted HTML. Versions prior to 0.4.3 do not HTML-entity-encode attribute values when serializing its sanitized output. In attributeString() (XHTMLPurifier.js, around line 148) the attribute value is concatenated directly into a double-quoted attribute without encoding. As a result, an attacker-controlled value in any allowed attribute (class, style, title, alt, src, href) can include a double-quote character to break out of the attribute and inject an additional attribute, such as a JavaScript event handler (for example onmouseover or onerror). The injected handler survives sanitization and executes when the output is rendered, which is a sanitizer bypass leading to cross-site scripting. The fix in version 0.4.3 HTML-entity-encodes attribute values before serialization.
A vulnerability in the xhtml-purifier Node.js library, affecting versions through 0.4.1, allows for cross-site scripting (XSS) attacks by injecting malicious JavaScript event handlers into HTML attributes. The issue arises because the library fails to properly HTML-entity-encode attribute values when serializing sanitized output. This oversight enables an attacker to manipulate attribute values in a way that bypasses the sanitizer and executes injected scripts when the HTML is rendered. The vulnerability is classified as moderate in severity.
Users can upgrade to xhtml-purifier version 0.4.3 or later, where this vulnerability has been patched.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Sep 24, 2026CISA-ADP
Assessed Sep 24, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/cstigler/node-xhtml-purifier/commit/21d461ad23e7bc9b3073693d5b51b9b8662044d3 | [email protected] | Source CodeVendor |
| https://github.com/cstigler/node-xhtml-purifier/security/advisories/GHSA-j8r4-32c5-33rc | [email protected] | AdvisoryRemedyVendor |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-116 | Improper Encoding or Escaping of Output | [email protected] |
| CWE-79 | Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| xhtml-purifier | <= 0.4.1 (semver) |
CPE
Remediation
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Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Sep 24, 2026 | CVE Modified | CISA-ADP |
| Sep 24, 2026 | New CVE Received | [email protected] |