CVE-2026-26019
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.
Does this matter?
Lower severity and a low EPSS score (0.39%). Track it; it rarely justifies an emergency change on its own.
Description
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.
- CVSS 3.1
- 4.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:N/A:N
- EPSS
- 0.39% probability · 32th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-918
- Affected
- langchain/langchain community
- Source
- security-advisories@github.com
References
- https://github.com/langchain-ai/langchainjs/commit/d5e3db0d01ab321ec70a875805b2f74aefdadf9dPatch
- https://github.com/langchain-ai/langchainjs/pull/9990Issue Tracking, Patch
- https://github.com/langchain-ai/langchainjs/releases/tag/%40langchain%2Fcommunity%401.1.14Release Notes
- https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-gf3v-fwqg-4vh7Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.