Improper Access ControlWeakness · CWE-284

CVE-2026-11326

MEDIUM · 6.0 CVSS v4.0 Published 2026-06-05

Mitigation only

No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.

See remediation →

67/100

Remediation priority · Elevated

Remotely reachable No privileges

Official description

NVD · unedited

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.

Technical summary

dbcve analysis · high confidence

OpenAI Atlas before version 1.2025.288.15 exposed privileged browser APIs (including browser history access and tab manipulation) to web content on *.openai.com origins. A cross-site scripting (XSS) vulnerability in forum.openai.com could be exploited to access these functions. The fix restricts API access to *.chatgpt.com only.

MitigationUpgrade to OpenAI Atlas version 1.2025.288.15 or later to restrict privileged API access to *.chatgpt.com origins.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown

From the vector

Attack vector: Network
Complexity: High
Privileges: None
Authentication: None
User interaction: P
Scope: X

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/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:N/R:X/V:D/RE:L/U:Green

Am I affected?

dbcve checks

Work through these to decide whether this CVE applies to you.

Identify the installed OpenAI Atlas version

Check your browser extension manager or application settings for the version number of OpenAI Atlas. In Chrome, go to chrome://extensions and enable Developer mode to see version details. In other browsers, check the respective extension or application settings.

Affected if The installed version is lower than 1.2025.288.15
Determine if you access forum.openai.com

Review your browser history or bookmarks for any visits to forum.openai.com or other *.openai.com subdomains.

Affected if You have visited or regularly visit forum.openai.com or other *.openai.com domains
Check browser extension permissions

Examine the permissions granted to the OpenAI Atlas browser extension in your browser's extension manager. Look for permission entries that include access to '*.openai.com' origins.

Affected if The extension has permissions granting access to *.openai.com domains
Test for exposed browser APIs

If you have developer tools knowledge, inspect whether JavaScript running on forum.openai.com can access privileged browser APIs such as window.history, browser.tabs, or similar functions. This typically requires examining the Content Security Policy and extension API bindings.

Affected if JavaScript from forum.openai.com can access browser history manipulation functions or tab management APIs

You are affected if you use OpenAI Atlas version below 1.2025.288.15 and have accessed or could access forum.openai.com, as the vulnerable version exposes privileged browser APIs to that origin.

Generated from the published advisory. Verify against your own configuration.

Remediation

dbcve · scoped

Mitigation available No clean upgrade yet — mitigate in the meantime

Mitigation

Upgrade to OpenAI Atlas version 1.2025.288.15 or later to restrict privileged API access to *.chatgpt.com origins.

Recommended fix High confidence

OpenAI Atlas 1.2025.288.15 or later

1. Identify the current version of OpenAI Atlas in use
2. Verify the installed version is earlier than 1.2025.288.15
3. Upgrade OpenAI Atlas to version 1.2025.288.15 or later
4. Verify the upgrade was successful by checking the version number
5. Confirm that privileged browser APIs are now restricted to *.chatgpt.com origins only

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory

Consultation2.0 h
Implementation1.0 h
Testing2.0 h
Review / QA1.0 h

6.0 hours of engineering $1,060

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Scan for this in your stack

Free · runs locally

dbcve dependency scanner

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References

Primary sources

www.hacktron.ai
nvd.nist.govNVD record

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-11326 in production — separate from our analysis above.

Notes0 Guidelines

Know something about CVE-2026-11326?

The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.

The version that genuinely resolved it — not the one the vendor claimed
A config change or rule that shut the vector down
A gotcha in the upgrade path that cost you an afternoon

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here

Verified mitigations, workarounds, and config changes
Version or environment caveats, and links to real fixes
No weaponised exploit code, or anything meant to cause harm
No spam, self-promotion, credentials, or personal data

At a glance

A fix existsA vendor remedy is published

Severity 6.0 Medium

Exploit likelihood EPSS, next 30 days 0.2%

Remediation

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Have this fixed 6 hrs · Moderate

Typical engagement from $1,060

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Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

Check your environment

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

Scan for this in your stack

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Practitioner notes

No notes yet

Official description

Technical summary

CVSS breakdown

Am I affected?

Remediation

References