LiquidJS's strip_html filter bypass via newline characters in HTML tags enables XSS
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 10.26.0
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
LiquidJS is a Shopify/GitHub Pages compatible template engine written in pure JavaScript. Versions 10.25.7 and below are vulnerable to XSS through a flaw in the strip_html filter logic. The strip_html filter is intended to remove HTML tags from a string before rendering, and is widely used as an XSS sanitizer. The implementation uses a regex whose catch-all branch (<.*?>) does not match line terminators, so any HTML tag containing a \n or \r character passes through unmodified. An attacker who can place a newline inside a tag (e.g. <img\nsrc=x\nonerror=alert(1)>) bypasses sanitization entirely, since browsers treat newlines as whitespace within a tag and execute the resulting onerror/onload/etc. handler. Exploitation is possible for applications that both render attacker-controlled strings via {{ x | strip_html }} to defend against HTML injection and do not separately HTML-escape that output (default behavior — outputEscape is unset by default). This issue has been fixed in version 10.26.0.
Timeline
- CVE published
- Record last updated
Affected versions
- harttle liquidjs
fixed in 10.26.0
- liquidjsnpm
fixed in 10.26.0