CVE-2026-27795

{"id": "CVE-2026-27795", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "CHANGED", "version": "3.1", "baseScore": 4.1, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "LOW"}, "impactScore": 1.4, "exploitabilityScore": 2.3}]}, "published": "2026-02-25T18:23:41.153", "references": [{"url": "https://github.com/langchain-ai/langchainjs/commit/2812d2b2b9fd9343c4850e2ab906b8cf440975ee", "source": "security-advisories@github.com"}, {"url": "https://github.com/langchain-ai/langchainjs/commit/d5e3db0d01ab321ec70a875805b2f74aefdadf9d", "source": "security-advisories@github.com"}, {"url": "https://github.com/langchain-ai/langchainjs/pull/9990", "source": "security-advisories@github.com"}, {"url": "https://github.com/langchain-ai/langchainjs/releases/tag/%40langchain%2Fcommunity%401.1.14", "source": "security-advisories@github.com"}, {"url": "https://github.com/langchain-ai/langchainjs/releases/tag/%40langchain%2Fcommunity%401.1.18", "source": "security-advisories@github.com"}, {"url": "https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-gf3v-fwqg-4vh7", "source": "security-advisories@github.com"}, {"url": "https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-mphv-75cg-56wg", "source": "security-advisories@github.com"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Primary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-918"}]}], "descriptions": [{"lang": "en", "value": "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."}], "lastModified": "2026-02-27T14:06:59.787", "sourceIdentifier": "security-advisories@github.com"}