Summary
Nokogiri < v1.13.6 does not type-check all inputs into the XML and HTML4 SAX parsers. For CRuby users, this may allow specially crafted untrusted inputs to cause illegal memory access errors (segfault) or reads from unrelated memory.
Severity
The Nokogiri maintainers have evaluated this as High 8.2 (CVSS3.1).
Mitigation
CRuby users should upgrade to Nokogiri >= 1.13.6.
JRuby users are not affected.
Workarounds
To avoid this vulnerability in affected applications, ensure the untrusted input is a String by calling #to_s or equivalent.
Credit
This vulnerability was responsibly reported by @agustingianni and the Github Security Lab.
References
- https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-xh29-r2w5-wx8m
- https://nvd.nist.gov/vuln/detail/CVE-2022-29181
- https://github.com/sparklemotion/nokogiri/commit/db05ba9a1bd4b90aa6c76742cf6102a7c7297267
- https://github.com/sparklemotion/nokogiri/releases/tag/v1.13.6
- https://securitylab.github.com/advisories/GHSL-2022-031_GHSL-2022-032_Nokogiri/
- https://github.com/advisories/GHSA-xh29-r2w5-wx8m