LangChain is a framework for building LLM-powered applications. Prior to version 1.1.8, a redirect-based Server-Side Request Forgery (SSRF) bypass exists in `RecursiveUrlLoader` in `@langchain/community`. The loader validates the initial URL but allows the underlying fetch to follow redirects automatically, which permits a transition from a safe public URL to an internal or metadata endpoint without revalidation. This is a bypass of the SSRF protections introduced in 1.1.14 (CVE-2026-26019). Users should upgrade to `@langchain/community` 1.1.18, which validates every redirect hop by disabling automatic redirects and re-validating `Location` targets before following them. In this version, automatic redirects are disabled (`redirect: "manual"`), each 3xx `Location` is resolved and validated with `validateSafeUrl()` before the next request, and a maximum redirect limit prevents infinite loops.
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Affected Vendors & Products
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History
Wed, 25 Feb 2026 18:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | LangChain is a framework for building LLM-powered applications. Prior to version 1.1.8, a redirect-based Server-Side Request Forgery (SSRF) bypass exists in `RecursiveUrlLoader` in `@langchain/community`. The loader validates the initial URL but allows the underlying fetch to follow redirects automatically, which permits a transition from a safe public URL to an internal or metadata endpoint without revalidation. This is a bypass of the SSRF protections introduced in 1.1.14 (CVE-2026-26019). Users should upgrade to `@langchain/community` 1.1.18, which validates every redirect hop by disabling automatic redirects and re-validating `Location` targets before following them. In this version, automatic redirects are disabled (`redirect: "manual"`), each 3xx `Location` is resolved and validated with `validateSafeUrl()` before the next request, and a maximum redirect limit prevents infinite loops. | |
| Title | LangChain Community: redirect chaining can lead to SSRF bypass via RecursiveUrlLoader | |
| Weaknesses | CWE-918 | |
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| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-02-25T18:42:52.277Z
Reserved: 2026-02-24T02:31:33.265Z
Link: CVE-2026-27795
No data.
Status : Received
Published: 2026-02-25T18:23:41.153
Modified: 2026-02-25T18:23:41.153
Link: CVE-2026-27795
No data.
OpenCVE Enrichment
No data.