Vulnerability in Nokogiri
CVE-2026-79772
Nokogiri versions before 1.19.1 fail to check the return value from xmlC14NExecute in the canonicalize method, returning an empty string on failure instead of raising an exception. Attackers can exploit this to bypass signature validation in downstream SAML libraries by providing invalid canonicalized XML that is incorrectly accepted as valid.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (25.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 26th percentile — 25.6% 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-wx95-c6cv-8532 (vendor-advisory, Vendor Advisory)
- www.vulncheck.com/advisories/nokogiri-before-unchecked-return-value-canonicalize (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-79772?
- CVE-2026-79772 is a medium-severity vulnerability in Nokogiri, classified under CWE-252. CVSS score: 5.3/10. Published 2026-08-25.
- How severe is CVE-2026-79772?
- Medium severity. CVSS v3 base score is 5.3 out of 10.