CVE-2026-53900

Severity CVSS v4.0:

Pending analysis

Type:

CWE-345 Insufficient Verification of Data Authenticity

Publication date:

16/06/2026

Last modified:

16/06/2026

Description

Firefox for iOS preserved cookies set on the initial PDF request across cross-origin HTTP redirects in TemporaryDocument, allowing a malicious site to inject arbitrary cookies into requests to an unrelated target domain. This vulnerability was fixed in Firefox for iOS 152.0.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N CVSS v3.1 Severity and Metrics:

Base Score: 4.30 MEDIUM
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): Required
Scope (S): Unchanged
Confidentiality (C): Low
Integrity (I): None
Availability (A): None

Base Score 3.x

4.30

Severity 3.x

MEDIUM

References to Advisories, Solutions, and Tools

https://bugzilla.mozilla.org/show_bug.cgi?id=2043204
https://www.mozilla.org/security/advisories/mfsa2026-56/