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CVE-2026-11326 OpenAI CVE debrief

A cross-site scripting vulnerability was discovered in OpenAI Atlas before version 1.2025.288.15. The issue exposed privileged browser APIs to web content on *.openai.com origins, which could be exploited via a cross-site scripting vulnerability in forum.openai.com. This could allow attackers to access browser history information and open or close tabs. The vulnerability has been addressed in OpenAI Atlas version 1.2025.288.15, which narrows access to these APIs to *.chatgpt.com.

Vendor
OpenAI
Product
OpenAI Atlas
CVSS
MEDIUM 6
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-05
Original CVE updated
2026-06-05
Advisory published
2026-06-05
Advisory updated
2026-06-05

Who should care

Users of OpenAI Atlas, particularly those using versions before 1.2025.288.15, should be aware of this vulnerability and upgrade to the latest version to mitigate the risk.

Technical summary

CVE-2026-11326 is a cross-site scripting vulnerability in OpenAI Atlas before 1.2025.288.15. It exposed privileged browser APIs to web content on *.openai.com origins, allowing access to browser history and tab control via a cross-site scripting vulnerability in forum.openai.com. The CVSS score for this vulnerability is 6, indicating a medium severity.

Defensive priority

MEDIUM

Recommended defensive actions

  • Upgrade to OpenAI Atlas version 1.2025.288.15 or later to mitigate the vulnerability.

Evidence notes

The vulnerability was reported by Hacktron, as referenced in their blog post [ref-4].

Official resources

CVE-2026-11326 was published on 2026-06-05T02:17:11.180Z and modified on 2026-06-05T18:17:04.343Z.