Vulnerability · Published Oct 30, 2026 · Assigned by GoogleCloud
CVE-2026-85268Cross-Site Scripting (XSS) in Firebase Auth Handler via Malicious Bundle ID
High 8.7
In plain English
A high-severity cross-site scripting in Identity Platform and Firebase Authentication from Google Cloud. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 48% of all known vulnerabilities).
Severity (CVSS 4.0)8.7High
Exploit odds (30 days)0.6%top 52.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Google Cloud | Identity Platform and Firebase Authentication | 0 – before 2026-08-14 |
Weakness: CWE-79 · 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