Out-of-bounds Write in zlib affects Nokogiri

Summary

Nokogiri v1.13.4 updates the vendored zlib from 1.2.11
to 1.2.12, which addresses CVE-2018-25032.
That CVE is scored as CVSS 7.4 “High” on the NVD record as of 2022-04-05.

Please note that this advisory only applies to the CRuby implementation of
Nokogiri < 1.13.4, and only if the packaged version of zlib is being used.
Please see this document
for a complete description of which platform gems vendor zlib. If you’ve
overridden defaults at installation time to use system libraries instead of
packaged libraries, you should instead pay attention to your distro’s zlib
release announcements.

Mitigation

Upgrade to Nokogiri >= v1.13.4.

Impact

CVE-2018-25032 in zlib

• Severity: High
• Type: CWE-787
  Out of bounds write
• Description: zlib before 1.2.12 allows memory corruption when
  deflating (i.e., when compressing) if the input has many distant matches.