IndexedDB should be cleared when leaving private browsing mode and it is not, the API for WKWebViewConfiguration was being used incorrectly…

published 2020-07-09 6y ago modified 2026-08-19 2mo ago also EUVD-2020-4726

cvss: 6.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 52%
public exploits: 0; none known

IndexedDB should be cleared when leaving private browsing mode and it is not, the API for WKWebViewConfiguration was being used incorrectly and requires the private instance of this object be deleted when leaving private mode. This vulnerability affects Firefox for iOS < 27.

Patch / fix

fixed in 1

Mozilla Firefox for iOS 27

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Exploit prediction

0.68% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:N/I:P/A:N

Affected products

Mozilla Firefox for iOS

Classification

Weakness

CWE-459 Incomplete Cleanup

References

mozilla.org /security/advisories/mfsa2020-23/
vendor-advisory
bugzilla.mozilla.org /show_bug.cgi?id=1646756
issue-tracking, permissions-required, vendor-advisory

Sources

CVE List CVE-2020-12414
NVD CVE-2020-12414

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