CVE-2026-4399
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.
NVD · uneditedPrompt injection vulnerability in 1millionbot Millie chatbot that occurs when a user manages to evade chat restrictions using Boolean prompt injection techniques (formulating a question in such a way that, upon receiving an affirmative response ('true'), the model executes the injected instruction), causing it to return prohibited information and information outside its intended context. Successful exploitation of this vulnerability could allow a malicious remote attacker to abuse the service for purposes other than those originally intended, or even execute out-of-context tasks using 1millionbot's resources and/or OpenAI's API key. This allows the attacker to evade the containment mechanisms implemented during LLM model training and obtain responses or chat behaviors that were originally restricted.
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.
dbcve analysis · moderate confidencePrompt injection vulnerability in 1millionbot Millie chatbot where attackers use Boolean-based prompt injection techniques to bypass chat restrictions. By formulating questions that yield affirmative responses, malicious instructions are executed, allowing unauthorized access to prohibited information and abuse of the service's OpenAI API resources.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data< 3.6.0CVSS 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.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
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.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify if you use 1millionbot Millie ChatbotReview your deployed applications and services to determine if the 1millionbot Millie chatbot is installed in your environmentAffected if The chatbot is present in your environment
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Check the installed Millie chatbot versionLocate the version information for your Millie chatbot installation (check product documentation for version file location or admin interface)Affected if The installed version is any version below 3.6.0
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Verify if chatbot input processing is enabledConfirm whether the chat/input processing module is active and accepting user queriesAffected if The chatbot is actively processing user inputs and the vulnerability is exploitable
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Review logs for Boolean-based prompt injection patternsSearch chatbot interaction logs for patterns like affirmative response triggers (e.g., 'yes', 'true', 'certainly', 'of course' chained with injection commands)Affected if Logs show attempts using Boolean-style prompts that may have bypassed restrictions
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Check for unauthorized OpenAI API usageReview OpenAI API usage metrics and access logs for unexpected or anomalous API calls originating from the chatbot serviceAffected if API usage shows spikes or calls to endpoints/content that were not initiated by legitimate user requests
You are affected if you have 1millionbot Millie Chatbot version below 3.6.0 with the chat functionality enabled and processing user inputs.
Generated from the published advisory. Verify against your own configuration.
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.
dbcve · scoped3.6.0
Implement robust input validation with sanitization layers to detect and block prompt injection patterns, enhance output filtering to catch prohibited content before delivery, and strengthen the LLM containment mechanisms through prompt engineering and fine-tuning.
3.6.0
- 1. Identify the current Millie Chatbot installation and verify the current version is below 3.6.0
- 2. Create a backup of the current Millie Chatbot configuration and data
- 3. Consult the official 1millionbot documentation or release notes for upgrade instructions specific to your deployment method
- 4. Upgrade Millie Chatbot to version 3.6.0 or later following the documented upgrade procedure
- 5. Verify the installation was successful and the new version is running
- 6. Test that the prompt injection containment mechanisms are functioning properly
- 7. Monitor the system for any unusual behavior after the upgrade
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation6.0 h
- Implementation20.0 h
- Testing12.0 h
- Review / QA6.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $12,288.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-4399 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-4399 in production — separate from our analysis above.
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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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.
- 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