{"cve":"CVE-2021-29958","nvd":{"published":"2021-06-24T14:15:10.143","modified":"2026-06-17T03:48:30.660","status":"Modified","description":"When a download was initiated, the client did not check whether it was in normal or private browsing mode, which led to private mode cookies being shared in normal browsing mode. This vulnerability affects Firefox for iOS < 34.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N","score":4.3},"cwes":["CWE-862"],"references":["https://bugzilla.mozilla.org/show_bug.cgi?id=1670127","https://www.mozilla.org/security/advisories/mfsa2021-25/","https://bugzilla.mozilla.org/show_bug.cgi?id=1670127","https://www.mozilla.org/security/advisories/mfsa2021-25/"],"products":["mozilla:firefox"],"source":"nvd","synced_at":"2026-10-19T21:20:07.141963181+00:00"},"epss":{"cve":"CVE-2021-29958","score":0.00671,"percentile":0.52024,"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."]}