CVE-2026-2950 — lodash
MEDIUMCVE-2026-2950 is a medium-severity (CVSS 6.5) CWE-1321 vulnerability in lodash. A fix is available for lodash — see the affected versions and patch details below.
lodash vulnerable to Prototype Pollution via array path bypass in `_.unset` and `_.omit`
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- 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-2026-2950.
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-2026-2950 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
Impact:
Lodash versions 4.17.23 and earlier are vulnerable to prototype pollution in the _.unset and _.omit functions. The fix for (CVE-2025-13465: https://github.com/lodash/lodash/security/advisories/GHSA-xxjr-mmjv-4gpg) only guards against string key members, so an attacker can bypass the check by passing array-wrapped path segments. This allows deletion of properties from built-in prototypes such as Object.prototype, Number.prototype, and String.prototype.
The issue permits deletion of prototype properties but does not allow overwriting their original behavior.
Patches:
This issue is patched in 4.18.0.
Workarounds:
None. Upgrade to the patched version.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | lodash | all versions | 4.18.0npm install lodash@4.18.0 |
| 📦npm | lodash-es | all versions | 4.18.0npm install lodash-es@4.18.0 |
| 📦npm | lodash-amd | all versions | 4.18.0npm install lodash-amd@4.18.0 |
| 📦npm | lodash.unset | ≥ 4.0.0&&< 4.18.0 | 4.18.0npm install lodash.unset@4.18.0 |
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 4.18.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-2950 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-2026-2950 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-2950. 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 Developer Hub 1.10 | rhdh/rhdh-hub-rhel9:1780930740 | RHSA-2026:24841 |
| Red Hat Hardened Images | nodejs25-main-25.9.0-1.1.hum1 | RHSA-2026:7378 |
| Red Hat Hardened Images | yarnpkg-main-1.22.22-18.1.hum1 | RHSA-2026:7655 |
| Red Hat Hardened Images | nodejs20-main-20.20.2-1.hum1 | RHSA-2026:9455 |
Frequently Asked Questions
Is CVE-2026-2950 in your dependencies?
O3 Security finds CVE-2026-2950 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.