Updated advisory posts against rubysec/ruby-advisory-db@fbe19bf

Author: jasnow

advisories/_posts/2026-06-19-GHSA-g9g8-vgvw-g3vf.md

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+---
+layout: advisory
+title: 'GHSA-g9g8-vgvw-g3vf (nokogiri): Possible invalid memory read when calling
+  `Nokogiri::XML::Node#initialize_copy_with_args` with incorrect argument type'
+comments: false
+categories:
+- nokogiri
+advisory:
+  gem: nokogiri
+  ghsa: g9g8-vgvw-g3vf
+  url: https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-g9g8-vgvw-g3vf
+  title: Possible invalid memory read when calling `Nokogiri::XML::Node#initialize_copy_with_args`
+    with incorrect argument type
+  date: 2026-06-19
+  description: |-
+    ## Summary
+
+    The protected copy helper behind Node#dup and #clone unwrapped its
+    source argument as an xmlNode without a type check.
+    Supplying a non-Node (e.g. a Namespace) made it read an xmlNs
+    out of bounds, crashing the process.
+
+    Nokogiri 1.19.4 performs a type check and raises TypeError when an
+    argument of invalid type is passed.
+
+     Only CRuby is affected. JRuby is not affected.
+
+    ## Severity
+
+    The Nokogiri maintainers have evaluated this as low severity.
+    This is only triggered by a programming error. It requires application
+    code to call the protected internal initialize_copy_with_args method
+    with an argument that is not a Nokogiri::XML::Node.
+    Nokogiri 1.19.4 now raises TypeError instead of reading out of bounds.
+    It cannot be triggered by untrusted input or through normal use of
+    the public API.
+
+    ## Mitigation
+
+    Upgrade to Nokogiri 1.19.4 or later. There is no workaround.
+
+    ## Credit
+
+    This issue was responsibly reported by Zheng Yu from depthfirst.com.
+  patched_versions:
+  - ">= 1.19.4"
+  related:
+    url:
+    - https://rubygems.org/gems/nokogiri/versions/1.19.4
+    - https://github.com/sparklemotion/nokogiri/releases/tag/v1.19.4
+    - https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-g9g8-vgvw-g3vf
+  notes: |
+    - no CVE number
+    - No [cvss_v2, cvss_v3, cvss_v4] on GHSA file
+---