LangChain: Unsafe deserialization of attacker-controlled LangChain objects through overly broad `load()` allowlists_CVE-2026-44843

{
    "lastseen": "",
    "description": "LangChain is a framework for building agents and LLM-powered applications. Prior to 0.3.85 and 1.3.3, LangChain contains older runtime code paths that deserialize run inputs, run outputs, or other application-controlled payloads using overly broad object allowlists. These paths may call load() with allowed_objects=\"all\". This does not enable arbitrary Python object deserialization, but it does allow any trusted LangChain-serializable object to be revived, which is broader than these runtime paths require. As a result, attacker-supplied LangChain serialized constructor dictionaries may cause trusted runtime paths to instantiate classes with untrusted constructor arguments. This vulnerability is fixed in 0.3.85 and 1.3.3.",
    "published": "2026-05-26T19:47:35.328Z",
    "modified": "2026-05-26T19:47:35.328Z",
    "type": "cve",
    "title": "LangChain: Unsafe deserialization of attacker-controlled LangChain objects through overly broad `load()` allowlists",
    "source": "GitHub_M",
    "references": "https://github.com/langchain-ai/langchain/security/advisories/GHSA-pjwx-r37v-7724",
    "id": "CVE-2026-44843",
    "bulletinFamily": "",
    "cwe": [
        "CWE-502"
    ],
    "cvelist": null,
    "sourceData": "langchain-ai langchain < 0.3.85\nlangchain-ai langchain >= 1.0.0a1, < 1.3.3",
    "sourceHref": "",
    "cvss": {
        "score": 8.2,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
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        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
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        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "langchain",
    "version": "< 0.3.85",
    "vendor": "langchain-ai",
    "ai_description": "",
    "ai_severity": "",
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    "ai_product": "",
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    "ai_score": 0
}