CVE-2019-1010266 is a medium-severity (CVSS 6.5) Uncontrolled Resource Consumption vulnerability in lodash. 1 public exploit or proof-of-concept reference is indexed, 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
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
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 |
Affected Products
lodashlodashResearch 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
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
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?
Find it across npm, RubyGems, including transitive dependencies.