CVE-2026-85268
Cross-Site Scripting (XSS) in Firebase Auth Handler via Malicious Bundle ID
Description
A Cross-Site Scripting (XSS) (CWE-79) vulnerability in the auth/handler in Google Cloud Identity Platform and Firebase Authentication versions prior to 2026-08-14 on iOS allows an unauthenticated remote attacker to execute arbitrary JavaScript using a malicious iOS bundle ID.
INFO
Published Date :
Oct. 30, 2026, 11:17 a.m.
Last Modified :
Oct. 30, 2026, 11:17 a.m.
Remotely Exploit :
Yes !
Source :
f45cbf4e-4146-4068-b7e1-655ffc2c548c
Affected Products
The following products are affected by CVE-2026-85268
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | HIGH | f45cbf4e-4146-4068-b7e1-655ffc2c548c | ||||
| CVSS 4.0 | HIGH | f45cbf4e-4146-4068-b7e1-655ffc2c548c |
Solution
- Update the iOS SDK to version 2026-08-14 or later.
- Ensure proper validation of bundle IDs in iOS applications.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-85268.
| URL | Resource |
|---|---|
| https://firebase.google.com/support/releases#auth-helper-fix |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-85268 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-85268
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-85268 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-85268 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by f45cbf4e-4146-4068-b7e1-655ffc2c548c
Oct. 30, 2026
Action Type Old Value New Value Added Description A Cross-Site Scripting (XSS) (CWE-79) vulnerability in the auth/handler in Google Cloud Identity Platform and Firebase Authentication versions prior to 2026-08-14 on iOS allows an unauthenticated remote attacker to execute arbitrary JavaScript using a malicious iOS bundle ID. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Amber Added CWE CWE-79 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/85xxx/CVE-2026-85268.json">CVE-2026-85268</a> Added Reference https://firebase.google.com/support/releases#auth-helper-fix