The vulnerability in dashbitco lazy_html (CVE-2026-92106) involves improper neutralization of input during web page generation, classified as CWE-79 (Cross-site Scripting). The functions LazyHTML.to_html/2 and LazyHTML.Tree.to_html/2 determine whether to escape element text based on tag names. However, style or script elements inside SVG or MathML foreign content are parsed with character references decoded but serialized as raw HTML text, causing text to be emitted unescaped. This allows encoded markup such as </style><img src=x onerror=...> inside <svg><style> to close the element on re-parse and become live markup. Applications that parse untrusted HTML, filter it, and serialize it for display are vulnerable because the payload is a plain text node that bypasses element or attribute filters. The affected versions are from 0.1.0 up to but not including 0.1.13.

An attacker can exploit this vulnerability to perform mutation-based cross-site scripting (XSS) attacks by injecting malicious HTML that is interpreted as live markup after a parse and serialize round-trip. This can lead to execution of arbitrary scripts in the context of the affected application. The CVSS 4.0 score is 2.3, indicating a low severity impact with network attack vector, low complexity, and requiring user interaction and partial attack complexity.

No explicit patch or remediation is provided in the available data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, applications should avoid parsing and serializing untrusted HTML with lazy_html or implement additional filtering mechanisms that account for this mutation XSS vector. Monitor vendor communications for updates and patches.