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 was being used for JS-to-native also, but it isn't needed in this case, and its usage was also leaking this token. This vulnerability affects Firefox for iOS < 25.
Affected products
mozilla: firefox mobile
References4
- www.mozilla.org/security/advisories/mfsa2020-15/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2020-15/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=1632387 Permissions Required
- bugzilla.mozilla.org/show_bug.cgi?id=1632387 Permissions Required
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 1% percentile: 60 · as of 2 November 2026
- CWE
- CWE-200
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