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

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

4.1 · CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:N/A:N

EPSS

• CVE-2026-26019: 0.40% estimated exploitation activity in the next 30 days; percentile 34.26 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Description 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 (e.g., https://example.com.attacker.com passes a startsWith check against https://example.com), 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 (169.254.169.254), localhost, or RFC 1918 addresses, and the crawler would fetch them without restriction. Impact An attacker who can influence the content of a page being…

Published by the source

11 Feb 2026, 15:13 UTC

Last modified by the source

10 Sep 2026, 03:50 UTC

Source last checked

26 Oct 2026, 12:42 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-gf3v-fwqg-4vh7

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-gf3v-fwqg-4vh7

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# Patch Next advisory brief: CVE-2026-26019

Advisory: @langchain/community affected by SSRF Bypass in RecursiveUrlLoader via insufficient URL origin validation
IDs: CVE-2026-26019, GHSA-gf3v-fwqg-4vh7
Record: https://patchnext.com/advisories/cve-2026-26019 (revision 2, source checked 26 Oct 2026, 12:42 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 4.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @langchain/community 1.1.14. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @langchain/community: affected <= 1.1.13; fixed in 1.1.14

## Suggested inspection (read-only)
- `npm ls @langchain/community --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on @langchain/community.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-gf3v-fwqg-4vh7 (OSV record GHSA-gf3v-fwqg-4vh7 lists affected ranges: npm @langchain/community >=0 <1.1.14 (fixed))
- Verified: https://github.com/advisories/GHSA-gf3v-fwqg-4vh7 (GitHub-reviewed advisory GHSA-gf3v-fwqg-4vh7 lists affected ranges: npm @langchain/community >=0 <=1.1.13)

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