Summary
Nokogiri 1.13.8, 1.13.9 fails to check the return value from xmlTextReaderExpand in the method Nokogiri::XML::Reader#attribute_hash. This can lead to a null pointer exception when invalid markup is being parsed.
For applications using XML::Reader to parse untrusted inputs, this may potentially be a vector for a denial of service attack.
Mitigation
Upgrade to Nokogiri >= 1.13.10.
Users may be able to search their code for calls to either XML::Reader#attributes or XML::Reader#attribute_hash to determine if they are affected.
Severity
The Nokogiri maintainers have evaluated this as High Severity 7.5 (CVSS3.1).
References
Credit
This vulnerability was responsibly reported by @davidwilemski.
References
- https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-qv4q-mr5r-qprj
- https://github.com/sparklemotion/nokogiri/commit/85410e38410f670cbbc8c5b00d07b843caee88ce
- https://github.com/sparklemotion/nokogiri/commit/9fe0761c47c0d4270d1a5220cfd25de080350d50
- https://nvd.nist.gov/vuln/detail/CVE-2022-23476
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/nokogiri/CVE-2022-23476.yml
- https://github.com/advisories/GHSA-qv4q-mr5r-qprj