CVE-2019-1010266 — lodash
MEDIUMCVE-2019-1010266 is a medium-severity (CVSS 6.5) Uncontrolled Resource Consumption vulnerability in lodash. 1 public exploit reference exists, so weaponization risk is real. A fix is available for lodash — see the affected versions and patch details below.
Regular Expression Denial of Service (ReDoS) in lodash
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2019-1010266 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
lodashnpmlodash-esnpmlodash-amdnpmDescription
lodash prior to 4.17.11 is affected by: CWE-400: Uncontrolled Resource Consumption. The impact is: Denial of service. The component is: Date handler. The attack vector is: Attacker provides very long strings, which the library attempts to match using a regular expression. The fixed version is: 4.17.11.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | lodash | ≥ 4.7.0&&< 4.17.11 | 4.17.11npm install lodash@4.17.11 |
| 📦npm | lodash-es | ≥ 4.7.0&&< 4.17.11 | 4.17.11npm install lodash-es@4.17.11 |
| 📦npm | lodash-amd | ≥ 4.7.0&&< 4.17.11 | 4.17.11npm install lodash-amd@4.17.11 |
| 💎RubyGems | lodash-rails | ≥ 4.7.0&&< 4.17.11 | 4.17.11bundle update lodash-rails --conservative |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for lodash, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update lodash to 4.17.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-1010266 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.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2019-1010266 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2019-1010266. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
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.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Quay 3 | quay/quay-rhel8:v3.6.0-62 | RHSA-2021:3917 |
Frequently Asked Questions
Is CVE-2019-1010266 in your dependencies?
O3 Security finds CVE-2019-1010266 across npm, RubyGems dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.