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}, {"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "CHANGED", "version": "3.1", "baseScore": 7.4, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 4.0, "exploitabilityScore": 2.8}]}, "published": "2026-02-25T18:23:41.153", "references": [{"url": "https://github.com/langchain-ai/langchainjs/commit/2812d2b2b9fd9343c4850e2ab906b8cf440975ee", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/langchain-ai/langchainjs/commit/d5e3db0d01ab321ec70a875805b2f74aefdadf9d", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/langchain-ai/langchainjs/pull/9990", "tags": ["Issue Tracking"], "source": "security-advisories@github.com"}, {"url": "https://github.com/langchain-ai/langchainjs/releases/tag/%40langchain%2Fcommunity%401.1.14", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/langchain-ai/langchainjs/releases/tag/%40langchain%2Fcommunity%401.1.18", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-gf3v-fwqg-4vh7", "tags": ["Not Applicable"], "source": "security-advisories@github.com"}, {"url": "https://github.com/langchain-ai/langchainjs/security/advisories/GHSA-mphv-75cg-56wg", "tags": ["Vendor Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Analyzed", "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."}, {"lang": "es", "value": "LangChain es un framework para construir aplicaciones impulsadas por LLM. Antes de la versi\u00f3n 1.1.8, existe una omisi\u00f3n de falsificaci\u00f3n de petici\u00f3n del lado del servidor (SSRF) basada en redirecci\u00f3n en `RecursiveUrlLoader` en `@langchain/community`. El cargador valida la URL inicial, pero permite que la recuperaci\u00f3n subyacente siga las redirecciones autom\u00e1ticamente, lo que permite una transici\u00f3n de una URL p\u00fablica segura a un endpoint interno o de metadatos sin revalidaci\u00f3n. Esto es una omisi\u00f3n de las protecciones de SSRF introducidas en 1.1.14 (CVE-2026-26019). Los usuarios deben actualizar a `@langchain/community` 1.1.18, que valida cada salto de redirecci\u00f3n deshabilitando las redirecciones autom\u00e1ticas y revalidando los objetivos de `Location` antes de seguirlos. En esta versi\u00f3n, las redirecciones autom\u00e1ticas est\u00e1n deshabilitadas (`redirect: 'manual'`), cada `Location` 3xx se resuelve y valida con `validateSafeUrl()` antes de la siguiente petici\u00f3n, y un l\u00edmite m\u00e1ximo de redirecciones evita bucles infinitos."}], "lastModified": "2026-04-13T14:15:35.920", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:langchain:langchain_community:*:*:*:*:*:node.js:*:*", "vulnerable": true, "matchCriteriaId": "82E0218B-5EC7-4779-9F3F-FF40F63DEA54", "versionEndExcluding": "1.1.18"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}