{"cve":"CVE-2021-40511","nvd":{"published":"2022-06-21T17:15:08.243","modified":"2026-06-17T04:07:04.173","status":"Modified","description":"OBDA systems’ Mastro 1.0 is vulnerable to XML Entity Expansion (aka “billion laughs”) attack allowing denial of service.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-776"],"references":["https://www.cyberiskvision.com/advisory/","https://www.obdasystems.com/mastro","https://www.cyberiskvision.com/advisory/","https://www.obdasystems.com/mastro"],"products":["obdasystems:mastro"],"source":"nvd","synced_at":"2026-10-19T21:32:39.174919249+00:00"},"epss":{"cve":"CVE-2021-40511","score":0.00943,"percentile":0.61045,"date":"2026-10-31"},"kev":null,"osv":[],"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."]}