Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:L) | Local access needed |
| Attack complexity (AC:L) | Low complexity |
| Attack requirements (AT:N) | No attack requirements |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:N) | No user interaction |
| Confidentiality (VC:H) | High confidentiality impact |
| Integrity (VI:H) | High integrity impact |
| Availability (VA:H) | High availability impact |
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/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:X/R:X/V:X/RE:X/U:X
About Lfnovo Open-Notebook
CVE-2026-33587 affects Lfnovo Open-Notebook, a product from Lfnovo. Before acting, confirm where Lfnovo Open-Notebook runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: Lack of user input sanitisation in Open Notebook v1.8.3 allows the application user to execute Python code (and subsequently OS commands) on the docker container via Server-Side Template Injection (SSTI) for user-created transformations.
The weakness class is Improper Input Validation. The software trusts input without checking it is safe.
Based on its CVSS vector, the flaw needs local or adjacent access, needs no login, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Lfnovo Open-Notebook |
| Affected versions | Open-Notebook before 1.8.4 |
| Published | May 7, 2026 |
| Last modified | Jun 17, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | a6d3dc9e-0591-4a13-bce7-0f5b31ff6158 |
How to detect it
- Inventory every instance of Lfnovo Open-Notebook and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Lfnovo Open-Notebook named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Lfnovo Open-Notebook to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-20: Improper Input Validation More CVEs with this weakness
Technical References
Frequently asked questions
Related CVEs
Lack of user input validation in the file upload functionality of Open Notebook v1.8.3 allows the application user to create or modify files on the docker container via path traversal.
An improper input validation, together with an overly permissive default CORS configuration in Open Notebook v1.8.1 allows remote attacker to trick a legitimate user to alter or delete arbitrary database entries via specially crafted malicious URL. Depending on the deployment, data exfiltration is also possible.
Improper Neutralization used in an OS Command in the container launcher in Google Gemini CLI (versions prior to 0.39.1) and run-gemini-cli GitHub Action (versions prior to 0.1.22) on headless CI platforms allows an unprivileged attacker to achieve pre-sandbox host-level code execution a maliciously crafted .gemini/.env file.
Budibase is a low code platform for creating internal tools, workflows, and admin panels. Prior to version 3.30.4, an unsafe `eval()` vulnerability in Budibase's view filtering implementation allows any authenticated user (including free tier accounts) to execute arbitrary JavaScript code on the server. This vulnerability ONLY affects Budibase Cloud (SaaS) - self-hosted deployments use native CouchDB views and are not vulnerable. The vulnerability exists in `packages/server/src/db/inMemoryView.ts` where user-controlled view map functions are directly evaluated without sanitization. The primary impact comes from what lives inside the pod's environment: the `app-service` pod runs with secrets baked into its environment variables, including `INTERNAL_API_KEY`, `JWT_SECRET`, CouchDB admin credentials, AWS keys, and more. Using the extracted CouchDB credentials, we verified direct database access, enumerated all tenant databases, and confirmed that user records (email addresses) are readable. Version 3.30.4 contains a patch.
Jellyfin is an open source self hosted media server. Versions prior to 10.11.7 contain a vulnerability chain in the subtitle upload endpoint (POST /Videos/{itemId}/Subtitles), where the Format field is not validated, allowing path traversal via the file extension and enabling arbitrary file write. This arbitrary file write can be chained into arbitrary file read via .strm files, database extraction, admin privilege escalation, and ultimately remote code execution as root via ld.so.preload. Exploitation requires an administrator account or a user that has been explicitly granted the "Upload Subtitles" permission. This issue has been fixed in version 10.11.7. If users are unable to upgrade immediately, they can grant non-administrator users Subtitle upload permissions to reduce attack surface.
Improper input validation in Azure Virtual Network Gateway allows an authorized attacker to execute code over a network.
Earn your free CTEM certification.
Learn to scope, prioritize, validate and mobilize fixes for CVEs like CVE-2026-33587 with a free CTEM certification.
Beginner / Practitioner / Program Leader
Explore certifications