CVE-2026-2950 lodash vulnerable to Prototype Pollution via array path bypass in `_.unset` and `_.omit`
Attackers can delete properties from built-in prototypes via array path bypass in lodash unset and omit functions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-2950?
CVE-2026-2950 is a medium-severity vulnerability in lodash, published on 31 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The _.unset and _.omit functions in Lodash are vulnerable to prototype pollution. The fix for CVE-2025-13465 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. The issue is patched from 4.18.0 to 4.18.1 depending on the package: lodash, lodash-es, and lodash-amd in 4.18.1, and the standalone lodash.unset and lodash.omit packages in 4.18.0.
Weakness: CWE-1321
Which versions are affected by CVE-2026-2950?
8 open source packages ship an affected version, including lodash, lodash-amd and lodash-es. It affects 4 products.
| Package | Affected | Fixed in |
|---|---|---|
lodash npm | All versions | 4.18.0 |
lodash npm | All versions | 4.18.0 |
lodash-amd npm | All versions | 4.18.0 |
lodash-amd npm | All versions | 4.18.0 |
lodash-es npm | All versions | 4.18.0 |
lodash-es npm | All versions | 4.18.0 |
2 more packages
lodash.unset npm | From 4.0.0 | 4.18.0 |
lodash.unset npm | From 4.0.0 | 4.18.0 |
Products include Lodash Lodash, Lodash Lodash-Amd, Lodash Lodash-Es, Lodash Lodash.unset.
How do I fix CVE-2026-2950?
Upgrade lodash to 4.18.0 or later.
Is CVE-2026-2950 being exploited?
There is no known exploitation of CVE-2026-2950 in the wild and no public exploit code.
Other vulnerabilities in lodash
- CVE-2026-4800 lodash vulnerable to Code Injection via `_.template` imports key names
- CVE-2020-8203 Prototype Pollution in lodash
- CVE-2021-23337 Command Injection
- CVE-2025-13465 Prototype Pollution Vulnerability in Lodash _.unset and _.omit functions
- CVE-2019-1010266 Regular Expression Denial of Service (ReDoS) in lodash
Sources
Also known as CLEANSTART-2026-WD42763, CLEANSTART-2026-XQ62650, CLSA-2026-1792102343, CLSA-2026-1792327052, CLSA-2026-1792762945, CLSA-2026-1792869761 and 41 more.