A Server-Side Request Forgery (SSRF) vulnerability in the @langchain/community package was urgently fixed by the LangChain development team This article explores attempts restrict crawling. . This vulnerability, known as CVE-2026-26019, impacts the web crawling tool RecursiveUrlLoader class.

It could be used by attackers to get around domain checks and gain access to cloud metadata endpoints or internal networks. Weak URL validation that uses basic string matching rather than appropriate origin checks is the root of the problem. The preventOutside option in vulnerable versions attempts to restrict crawling to the starting domain, such as https://example.com. But because it makes use of String.startsWith(), attackers can create URLs like https://example.com.attacker.com.

By deceiving the check, this prefix technique allows malicious links to retrieve data from any location. Even worse, outdated code exposed services on internal networks by ignoring localhost and private IPs.

In order to force fetches from AWS metadata at 169.254.169.254, Google Cloud, or Azure endpoints, threat actors could insert links into crawled pages. IAM credentials are frequently obtained through such access, allowing for complete cloud takeovers. CVE ID CVSS Score Description CVE-2026-26019 6.1 (Medium) Inadequate URL origin validation in @langchain/community RecursiveUrlLoader results in an SSRF bypass that grants access to cloud metadata and internal services.

Versions of the Package Affected @langchain/community <= 1.1.13 1.1.14 is the patched version. With significant modifications, LangChain resolved this in version 1.1.14. For precise matches on scheme, hostname, and port, developers now use the URL API. Prior to requests, a new SSRF module blocks loopback (127.0.0.1), metadata services, and private IPs (such as 192.168.0.0/16 and 10.0.0.0/8).

Although there are currently no publicly available IOCs, such as hashes or domains, exploitation necessitates manipulating crawled content.

Developers need to update to 1.1.14 immediately. As a workaround, either isolate apps from internal networks or omit RecursiveUrlLoader on untrusted inputs. This patch guards against credential theft in AI-powered applications that use LangChain to import data.

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