CVE-2026-57236 (GCVE-0-2026-57236)
Vulnerability from cvelistv5 – Published: 2026-06-25 14:29 – Updated: 2026-06-25 15:32
VLAI
EPSS
VEX
Title
Nokogiri: Possible Use-After-Free when `Nokogiri::XML::Document#encoding=` raises an exception
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-25 15:32 UTC
CWE
- CWE-416 - Use After Free
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/sparklemotion/nokogiri/securit… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| sparklemotion | nokogiri |
Affected:
< 1.19.4
|
guessed |
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