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CVE-2026-85268

Cross-Site Scripting (XSS) in Firebase Auth Handler via Malicious Bundle ID

CVSS score

8.7

EPSS probability

—

Risk score

0.9

Published

3 h ago

OverviewPublic Exploits (0)NewsroomVulnerability Timeline
Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

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Vulnerability description

DayBreach AI Explanation

Verified against sources

CVE-2026-85268: XSS Vulnerability in Firebase Auth Handler

Sources read

1

Source agreement

Tam uyum

Evidence confidence

%55

Short explanation

A Cross-Site Scripting (XSS) (CWE-79) vulnerability affects the auth/handler in Google Cloud Identity Platform and Firebase Authentication on iOS for versions prior to 2026-08-14 [S0]. An unauthenticated remote attacker can execute arbitrary JavaScript using a malicious iOS bundle ID [S0].

Why does it matter?

This vulnerability can be exploited remotely without authentication, posing a high security risk [S0]. Attackers can achieve significant impact on targeted systems [S0].

What should be done?

  • Monitor vendor advisories and updates
  • Apply available updates to affected components
Chain of evidence and sources2 verified claims

Google Cloud Identity Platform ve Firebase Authentication üzerinde bir XSS (CWE-79) zafiyeti bulunmaktadır [S0].

S0 · daybreach-canonicalS1 · cvelist

Kimlik doğrulaması yapmamış uzak bir saldırgan kötü amaçlı bir iOS bundle ID kullanarak rastgele JavaScript çalıştırabilir [S0].

S0 · daybreach-canonicalS1 · cvelist
Show the technical text from the sources

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.

CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/U:Amber

CWE: CWE-79

This explanation was compiled automatically from the source records. Scores, active exploitation, patch and exploit status come straight from the sources.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-85268 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1Google CloudIdentity Platform and Firebase Authentication View
Total affected vendors: 1|Products: 1

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
8.7CVSS V4_0HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/U:AmberCVE CNA
8.7CVSS V40HIGHCVSS:4.0/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:AmberNVD

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-85268 is associated with the following CWEs:

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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.

CAPEC-66: SQL InjectionCAPEC-126: Path TraversalCAPEC-28: OS Command Injection

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsGerekmiyor
User—

Official Sources and Advisories

https://firebase.google.com/support/releases#auth-helper-fixvendor-advisory

CVSS Vector Radar Chart

8.7 / 10
Attack VectorNetworkComplexityLowPrivilegesNoneUser Interact.RequiredConfidentialityLowIntegrityNoneAvailabilityHigh

Vulnerability Scoring Details

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/U:Amber
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone required
User InteractionP
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)P
Availability (Erişilebilirlik)High

Yama durumu bilinmiyor

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Follow the vendor

GC
Google Cloud logo
Google Cloud

Weakness Type (CWE & CAPEC)

CWE-79

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CVE-2026-85268 · Cross-Site Scripting (XSS) in Firebase Auth…