CVE-2026-26019CWE-918

@langchain/community affected by SSRF Bypass in RecursiveUrlLoader via insufficient URL origin validation

Medium · published February 11, 2026

CVSS v3.1
4.1
EPSS
0%
Percentile
32.3
In the wild
Unconfirmed
What it is

LangChain is a framework for building LLM-powered applications. Prior to 1.1.14, the RecursiveUrlLoader class in @langchain/community is a web crawler that recursively follows links from a starting URL. Its preventOutside option (enabled by default) is intended to restrict crawling to the same site as the base URL. The implementation used String.startsWith() to compare URLs, which does not perform semantic URL validation. An attacker who controls content on a crawled page could include links to domains that share a string prefix with the target, causing the crawler to follow links to attacker-controlled or internal infrastructure. Additionally, the crawler performed no validation against private or reserved IP addresses. A crawled page could include links targeting cloud metadata services, localhost, or RFC 1918 addresses, and the crawler would fetch them without restriction. This vulnerability is fixed in 1.1.14.

The record
Technical detail
CVSS v3.1
4.1 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00393 · 32.3th percentile
Weakness
CWE-918 · Server-Side Request Forgery (SSRF)
Published
2026-02-11T21:11Z
EPSS history
Timeline
  • 11 FEB 21:11Z
    @langchain/community affected by SSRF Bypass in RecursiveUrlLoader via insufficient URL origin validation
    cvelistv5