CVE-2026-11326CWE-284

OpenAI Atlas before 1.2025.288.15 exposed privileged browser APIs to web content on *.openai.com origins

Medium · published June 5, 2026

CVSS v4.0
6.0
EPSS
0%
Percentile
11.1
In the wild
Unconfirmed
What it is

OpenAI Atlas before 1.2025.288.15 exposed privileged browser APIs to web content on *.openai.com origins. A cross-site scripting vulnerability in forum.openai.com could be used to access these functions, allowing access to browser history information and the ability to open or close tabs. OpenAI Atlas 1.2025.288.15 narrows access to these APIs to *.chatgpt.com; users should upgrade to 1.2025.288.15 or later.

The record
Technical detail
CVSS v4.0
6.0 · MEDIUM
Vector
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/AU:N/V:D/RE:L/U:Green
EPSS
0.00214 · 11.1th percentile
Weakness
CWE-284 · Improper Access Control
Published
2026-06-05T00:12Z
EPSS history
Timeline
  • 05 JUN 00:12Z
    OpenAI Atlas before 1.2025.288.15 exposed privileged browser APIs to web content on *.openai.com origins
    cvelistv5