{"cve":"CVE-2020-1911","nvd":{"published":"2020-09-04T03:15:09.700","modified":"2026-06-17T03:02:36.037","status":"Modified","description":"A type confusion vulnerability when resolving properties of JavaScript objects with specially-crafted prototype chains in Facebook Hermes prior to commit fe52854cdf6725c2eaa9e125995da76e6ceb27da allows attackers to potentially execute arbitrary code via crafted JavaScript. Note that this is only exploitable if the application using Hermes permits evaluation of untrusted JavaScript. Hence, most React Native applications are not affected.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-843"],"references":["https://github.com/facebook/hermes/commit/fe52854cdf6725c2eaa9e125995da76e6ceb27da","https://www.facebook.com/security/advisories/cve-2020-1911","https://github.com/facebook/hermes/commit/fe52854cdf6725c2eaa9e125995da76e6ceb27da","https://www.facebook.com/security/advisories/cve-2020-1911"],"products":["facebook:hermes"],"source":"nvd","synced_at":"2026-10-19T21:09:20.498348299+00:00"},"epss":{"cve":"CVE-2020-1911","score":0.02003,"percentile":0.80789,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-f5x2-xv93-4p23","url":"https://osv.dev/vulnerability/GHSA-f5x2-xv93-4p23","summary":"Access of Resource Using Incompatible Type in Facebook Hermes","modified":"2023-11-08T04:02:45.072039Z","packages":[{"ecosystem":"npm","name":"hermes-engine","purl":"pkg:npm/hermes-engine","ranges":["<0.5.2"],"fixed":["0.5.2"]}]}],"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."]}