Nokogiri is an open source XML and HTML library for the Ruby programming language. Prior to 1.19.4, calling Document#encoding= with an invalid encoding (e.g., a non-string, or a string containing a null byte) raises an exception, but only after freeing the document's current encoding string without replacing it. The document is left referencing freed memory, so the next call to Document#encoding reads invalid memory, which can cause a segfault or leak freed bytes into a Ruby String. Affects the CRuby (libxml2) implementation only; JRuby is not affected. This vulnerability is fixed in 1.19.4.
{
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/57xxx/CVE-2026-57236.json",
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-416"
]
}{
"cpe": "cpe:2.3:a:nokogiri:nokogiri:*:*:*:*:*:ruby:*:*",
"source": [
"AFFECTED_FIELD",
"CPE_RANGE"
],
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "1.19.4"
}
]
}