CVE-2019-11068 is a critical-severity (CVSS 9.8) vulnerability in nokogiri. A fix is available for nokogiri — see the affected versions and patch details below.
Nokogiri vulnerable to libxslt protection mechanism bypass
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2019-11068.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
nokogiriReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
A dependency of Nokogiri, libxslt through 1.1.33 allows bypass of a protection mechanism because callers of xsltCheckRead and xsltCheckWrite permit access even upon receiving a -1 error code. xsltCheckRead can return -1 for a crafted URL that is not actually invalid and is subsequently loaded.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | nokogiri | all versions | 1.10.3bundle update nokogiri --conservative |
Affected Products
ubuntu linuxcanonicaldebian linuxdebianfedorafedoraprojectactive iq unified managernetappcloud backupnetappe-series santricity management plug-insnetappDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for nokogiri, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update nokogiri to 1.10.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-11068 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Red Hat OpenStack will consume fixes from the base Red Hat Enterprise Linux Operating System. Therefore the package provided by Red Hat OpenStack has been marked as will not fix.
This flaw only applies to applications compiled against libxml2 which use xsltCheckRead and xsltCheckWrite functions and/or allow users to load arbitrary URLs to be parsed via libxml2. In all other cases, applications are not vulnerable.Source: Red Hat security advisory for CVE-2019-11068 (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 7 | libxslt-0:1.1.28-6.el7 | RHSA-2020:4005 |
| Red Hat Enterprise Linux 8 | libxslt-0:1.1.32-5.el8 | RHSA-2020:4464 |
Frequently Asked Questions
Is CVE-2019-11068 in your dependencies?
Find it across RubyGems, including transitive dependencies.