CVE-2026-53899

Firefox for iOS used partial domain matching when attaching cookies to PDF requests, allowing a malicious site on a suffix domain to receive cookies belonging to the target site. This vulnerability was fixed in Firefox for iOS 152.0.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2042909	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-56/	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:mozilla:firefox_mobile:*:*:*:*:*:iphone_os:*:*

History

26 Oct 2026, 00:10

Type	Values Removed	Values Added
Summary		(es) Firefox para iOS utilizaba la coincidencia parcial de dominios al adjuntar cookies a solicitudes de PDF, permitiendo que un sitio malicioso en un dominio de sufijo recibiera cookies pertenecientes al sitio objetivo. Esta vulnerabilidad se corrigió en Firefox para iOS 152.0.

Information

Published : 2026-06-16 13:16

Updated : 2026-10-26 00:10

NVD link : CVE-2026-53899

Mitre link : CVE-2026-53899

CVE.ORG link : CVE-2026-53899

JSON object : View

Products Affected

mozilla

firefox_mobile

CWE

CWE-345

Insufficient Verification of Data Authenticity

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