{"cve":"CVE-2024-1455","nvd":{"published":"2024-03-26T14:15:08.450","modified":"2026-06-17T07:04:16.863","status":"Analyzed","description":"A vulnerability in the langchain-ai/langchain repository allows for a Billion Laughs Attack, a type of XML External Entity (XXE) exploitation. By nesting multiple layers of entities within an XML document, an attacker can cause the XML parser to consume excessive CPU and memory resources, leading to a denial of service (DoS).","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":5.9},"cwes":["CWE-776"],"references":["https://github.com/langchain-ai/langchain/commit/727d5023ce88e18e3074ef620a98137d26ff92a3","https://huntr.com/bounties/4353571f-c70d-4bfd-ac08-3a89cecb45b6","https://github.com/langchain-ai/langchain/commit/727d5023ce88e18e3074ef620a98137d26ff92a3","https://huntr.com/bounties/4353571f-c70d-4bfd-ac08-3a89cecb45b6"],"products":["langchain:langchain"],"source":"nvd","synced_at":"2026-10-19T21:47:51.568503435+00:00"},"epss":{"cve":"CVE-2024-1455","score":0.00764,"percentile":0.55419,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-q84m-rmw3-4382","url":"https://osv.dev/vulnerability/GHSA-q84m-rmw3-4382","summary":"LangChain's XMLOutputParser vulnerable to XML Entity Expansion","modified":"2026-07-07T17:56:44.869554230Z","packages":[{"ecosystem":"PyPI","name":"langchain-core","purl":"pkg:pypi/langchain-core","ranges":["<0.1.35"],"fixed":["0.1.35"]}]},{"id":"PYSEC-2026-1519","url":"https://osv.dev/vulnerability/PYSEC-2026-1519","summary":"LangChain's XMLOutputParser vulnerable to XML Entity Expansion","modified":"2026-07-07T17:46:47.138281611Z","packages":[{"ecosystem":"PyPI","name":"langchain-core","purl":"pkg:pypi/langchain-core","ranges":["<0.1.35"],"fixed":["0.1.35"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}