{"cve":"CVE-2021-3918","nvd":{"published":"2021-11-13T09:15:06.737","modified":"2026-06-17T04:05:59.267","status":"Modified","description":"json-schema is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')","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-1321"],"references":["https://github.com/kriszyp/json-schema/commit/22f146111f541d9737e832823699ad3528ca7741","https://huntr.dev/bounties/bb6ccd63-f505-4e3a-b55f-cd2662c261a9","https://lists.debian.org/debian-lts-announce/2022/12/msg00013.html","https://github.com/kriszyp/json-schema/commit/22f146111f541d9737e832823699ad3528ca7741","https://huntr.dev/bounties/bb6ccd63-f505-4e3a-b55f-cd2662c261a9"],"products":["debian:debian_linux","json-schema_project:json-schema"],"source":"nvd","synced_at":"2026-10-19T21:24:39.218183596+00:00"},"epss":{"cve":"CVE-2021-3918","score":0.0383,"percentile":0.90089,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-896r-f27r-55mw","url":"https://osv.dev/vulnerability/GHSA-896r-f27r-55mw","summary":"json-schema is vulnerable to Prototype Pollution","modified":"2025-01-17T21:31:38Z","packages":[{"ecosystem":"npm","name":"json-schema","purl":"pkg:npm/json-schema","ranges":["<0.4.0"],"fixed":["0.4.0"]}]}],"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."]}