CVE-2026-103417: Vulnerability in Mozilla Firefox for iOS
Description
A vulnerability in Firefox for iOS allowed autofill of saved credentials into a new page after cross-origin navigation if the saved-login UI was open. The autofill was not restricted to the original page, potentially exposing credentials to unintended origins. This issue was fixed in Firefox for iOS version 157.1.
Affected software
Mozilla
Firefox for iOS
pkg:github/mozilla/firefox-iosRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-103417 describes a vulnerability in Mozilla Firefox for iOS where the autofill feature could improperly fill saved login credentials into a new page following cross-origin navigation while the saved-login UI was active. The autofill mechanism did not verify that the page origin remained the same, allowing credentials to be filled into a different origin than intended. This flaw was addressed and fixed in Firefox for iOS version 157.1.
Potential Impact
The vulnerability could lead to saved credentials being autofilled into a page from a different origin than the one that originally requested the autofill, potentially exposing user credentials to unintended or malicious sites. This could increase the risk of credential leakage or unauthorized access if exploited.
Mitigation Recommendations
This vulnerability has been fixed in Firefox for iOS version 157.1. Users and administrators should update to this version or later to remediate the issue. No additional mitigation steps are required once the update is applied.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-30T14:48:16.869Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-105/","vendor":"Mozilla"}]
Threat ID: 6acde2692cdf04f6563ccc11
Added to database: 10/13/2026, 07:48:57 UTC
Last enriched: 10/13/2026, 08:03:28 UTC
Last updated: 10/13/2026, 08:08:22 UTC
Views: 6
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