https://vulnerability.circl.lu/rss/recent/all/10 Most recent entries from all 2026-09-30T06:46:26.900396+00:00 Vulnerability-Lookup info@circl.lu python-feedgen Contains only the most 10 recent entries. https://vulnerability.circl.lu/vuln/cve-2026-57435 CVE-2026-57435 — Nokogiri: Possible Use-After-Free when setting an attribute value via `Nokogiri::XML::Attr#value=` or `#content=` 2026-09-30T06:46:26.929633+00:00

Affected: sparklemotion nokogiri

Nokogiri is an open source XML and HTML library for the Ruby programming language. Prior to 1.19.4, Nokogiri’s CRuby native extension could leave a Ruby wrapper pointing to freed memory when replacing the value of an XML attribute. If Ruby code had already accessed an attribute child node, Nokogiri::XML::Attr#value= could free the underlying native child node while the wrapper remained reachable through the document node cache. A later use of the freed child node or a Ruby GC mark could dereference an invalid pointer, causing an invalid read and a possible segfault. This vulnerability is fixed in 1.19.4.

 https://vulnerability.circl.lu/vuln/ghsa-phwj-rprq-35pp GHSA-phwj-rprq-35pp — Nokogiri: Possible Use-After-Free when setting an attribute value via `Nokogiri::XML::Attr#value=` or `#content=` 2026-09-30T06:46:26.929759+00:00

Affected: RubyGems: nokogiri

### Summary

Nokogiri’s CRuby native extension could leave a Ruby wrapper pointing to freed memory when replacing the value of an XML attribute. If Ruby code had already accessed an attribute child node, `Nokogiri::XML::Attr#value=` could free the underlying native child node while the wrapper remained reachable through the document node cache. A later use of the freed child node or a Ruby GC mark could dereference an invalid pointer, causing an invalid read and a possible segfault.

Nokogiri 1.19.4 preserves any already-wrapped attribute child nodes before replacing the attribute value.

JRuby is not affected.

### Severity

The Nokogiri maintainers have evaluated this as low severity. Reaching it requires an unusual API-usage pattern that does not arise during normal use. The application must directly access an attribute's child node and then replace that same attribute's value via `Attr#value=` or `#content=`. Nokogiri 1.19.4 makes this pattern safe with no change to the public API. Already-wrapped attribute child nodes are preserved before the value is replaced.

### Mitigation

Upgrade to Nokogiri 1.19.4 or later.

As a workaround, avoid accessing attribute child nodes directly via `Attr#child` or similar before mutating the same attribute’s value.

### Credit

This issue was responsibly reported by Zheng Yu from depthfirst.com.