SB2026041144 - Prototype pollution in langsmith-sdk
Published: April 11, 2026
Security Bulletin ID
SB2026041144
Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Prototype pollution (CVE-ID: CVE-2026-40190)
The vulnerability allows a remote attacker to modify object prototype attributes.
The vulnerability exists due to improperly controlled modification of object prototype attributes in the internal lodash set() utility used by the createAnonymizer() API when processing attacker-controlled object keys in data being anonymized. A remote attacker can supply crafted keys using the constructor.prototype traversal path to modify object prototype attributes.
The issue can affect all objects in the Node.js process.
Remediation
Install update from vendor's website.