Description
For native-to-JS bridging the app requires a unique token to be passed that ensures non-app code can't call the bridging functions. That token could leak when used for downloading files. This vulnerability affects Firefox for iOS < 26.
Affected products
mozilla: firefox mobile
References4
- bugzilla.mozilla.org/show_bug.cgi?id=1631739 Issue TrackingPermissions RequiredVendor Advisory
- www.mozilla.org/security/advisories/mfsa2020-19/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=1631739 Issue TrackingPermissions RequiredVendor Advisory
- www.mozilla.org/security/advisories/mfsa2020-19/ Vendor Advisory
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N - EPSS — exploit probability
- 1% percentile: 56 · as of 2 November 2026
- CWE
- CWE-79
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