Vulnerability in Sparklemotion Nokogiri
CVE-2026-79769
Nokogiri versions before 1.19.4 contain a possible invalid (out-of-bounds) memory read in the protected internal Node#initialize_copy_with_args helper behind Node#dup and #clone, which unwrapped its source argument as an xmlNode without a type check. If application code calls this protected method with a non-Node argument (e.g., a Namespace), it reads an xmlNs out of bounds, crashing the process. This is only triggerable by a programming error and cannot be triggered by untrusted input or normal use of the public API. Only CRuby is affected. Version 1.19.4 adds a type check and raises TypeError.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.003 (21.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 22nd percentile — 21.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
Weakness classification (CWE)
References
- github.com/sparklemotion/nokogiri/security/advisories/GHSA-g9g8-vgvw-g3vf (vendor-advisory)
- www.vulncheck.com/advisories/nokogiri-before-invalid-memory-read-via-initialize… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-79769?
- CVE-2026-79769 is a medium-severity vulnerability in Sparklemotion Nokogiri, classified under Access of Resource Using Incompatible Type (Type Confusion). CVSS score: 5.5/10. Published 2026-08-25.
- How severe is CVE-2026-79769?
- Medium severity. CVSS v3 base score is 5.5 out of 10.