CVE-2026-2950

Description

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.

CVSS Metrics

• v3.1•MEDIUM•Score: 6.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
• v3.1•MEDIUM•Score: 5.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

EPSS Trends

Current EPSS score: 0.32%• Percentile: 24%

Techniques & Countermeasures

• CWE-1321•Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

  The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype.

Affected Systems

• lodash•lodash

  ≥ 4.17.23, < 4.18.0 | ≥ 4.0.0, < 4.17.23

• lodash•lodash-amd

  ≥ 4.17.23, < 4.18.0 | ≥ 4.0.0, < 4.17.23

• lodash•lodash-es

  ≥ 4.17.23, < 4.18.0 | ≥ 4.0.0, < 4.17.23

• lodash•lodash.unset

  ≥ 4.0.0, < 4.18.0 | ≥ 4.0.0

• Npm•lodash

  < 4.18.0

• Npm•lodash-amd

  < 4.18.0

• Npm•lodash-es

  < 4.18.0

• Npm•lodash.unset

  ≥ 4.0.0, < 4.18.0

References (4)

• https://github.com/lodash/lodash/security/advisories/GHSA-xxjr-mmjv-4gpg
• https://github.com/lodash/lodash/security/advisories/GHSA-f23m-r3pf-42rh
• https://nvd.nist.gov/vuln/detail/CVE-2026-2950
• https://github.com/lodash/lodash