{"answers":{"affected":"2 open source packages ship an affected version, including langsmith. It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40190 exists.","fix":"Upgrade langsmith to 0.5.18 or later.","what":"CVE-2026-40190 is a medium-severity vulnerability in langchain-ai langsmith-sdk, published on 10 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-40190 and fix it if it is affected.\n\nWhat it is: CVE-2026-40190 is a medium-severity vulnerability in langchain-ai langsmith-sdk, published on 10 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40190 exists.\n\nAffected packages and fixed versions:\n- langsmith (npm): affected all versions; fixed in 0.5.18\n- langsmith (npm): affected all versions; fixed in 0.5.18\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-40190/ (Markdown: https://insights.sbomify.com/CVE-2026-40190/index.md)","id":"CVE-2026-40190","markdown":"https://insights.sbomify.com/CVE-2026-40190/index.md","name":"CVE-2026-40190","record":{"aliases":["ECHO-4586-52d3-1687","GHSA-fw9q-39r9-c252","MINI-2r39-prj9-w236","MINI-2rgp-5c7v-fjpq","MINI-4fqr-xrww-2298","MINI-97h9-5638-wwrf","MINI-ff9f-8mfv-cc3w","MINI-hf29-x68f-gmh5","MINI-jh8c-2fjg-grg2","MINI-jwqq-43m6-q59j","MINI-m7vc-x936-jfh8","MINI-mq5x-4gg9-qgm9","MINI-rmw6-r33p-xwjq","ROOT-APP-NPM-CVE-2026-40190"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["code_execution","privilege_escalation"],"network_reachable":"yes","non_default_config":false,"product_category":"LangSmith JavaScript SDK","requires_auth":"none","summary":"Prototype pollution in LangSmith SDK allows attackers to modify Object.prototype via crafted keys, potentially leading to code execution or privilege escalation.","user_interaction":"not_required","vuln_class":"other"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"langsmith","vendor":"langchain"}],"cvss":{"score":5.6,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L","version":"3.1"},"cwes":[{"id":"CWE-1321","name":"Improperly Controlled Modification of Object Prototype Attributes"}],"description":"LangSmith Client SDKs provide SDK's for interacting with the LangSmith platform. Prior to 0.5.18, the LangSmith JavaScript/TypeScript SDK (langsmith) contains an incomplete prototype pollution fix in its internally vendored lodash set() utility. The baseAssignValue() function only guards against the __proto__ key, but fails to prevent traversal via constructor.prototype. This allows an attacker who controls keys in data processed by the createAnonymizer() API to pollute Object.prototype, affecting all objects in the Node.js process. This vulnerability is fixed in 0.5.18.","ecosystems":["npm"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"LangSmith Client SDKs has Prototype Pollution in langsmith-sdk via Incomplete `__proto__` Guard in Internal lodash `set()`","id":"CVE-2026-40190","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":null,"products":[],"type":"other","year":"2026"},"n_packages":2,"n_references":1,"next":{"headline":"ClearanceKit has a policy bypass via dual-path Endpoint Security events checking only source path","id":"CVE-2026-40191"},"packages":[{"ecosystem":"npm","fixed":["0.5.18"],"introduced":["0"],"last_affected":[],"package":"langsmith","purl":null,"source":"GHSA-fw9q-39r9-c252"},{"ecosystem":"npm","fixed":["0.5.18"],"introduced":["0"],"last_affected":[],"package":"langsmith","purl":"pkg:npm/langsmith","source":"GHSA-fw9q-39r9-c252"}],"prev":{"headline":"goshs has a file-based ACL authorization bypass in goshs state-changing routes","id":"CVE-2026-40189"},"products":["langsmith-sdk"],"published":"2026-04-10","related":[{"cvss_score":8.5,"headline":"LangSmith Studio has URL Parameter Injection Vulnerability that Enables Token Theft via Malicious baseUrl","id":"CVE-2026-25750","kev_date_added":null,"published":"2026-03-04"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-04-13","vendors":["langchain-ai"]},"summary":"Prototype pollution in LangSmith SDK allows attackers to modify Object.prototype via crafted keys, potentially leading to code execution or privilege escalation.","url":"https://insights.sbomify.com/CVE-2026-40190/"}