# Developer Tool Lockdown Kit: Verify AI Extensions, Rotate Credentials, Confirm Patches

This kit helps a small business owner and their developer or IT person check whether any fake AI-branded tool is installed, deal with a possibly exposed laptop, and get written confirmation that the exploited flaws in GitLab, Cisco ASA/FTD, the Linux kernel and VMware are patched. Print it, work through it in one sitting, and keep the filled-in worksheet. It reflects public reporting as of October 31, 2026. Some facts, such as whether any data was actually stolen, were still unknown when this was written.

## Checklist

- [ ] List every AI coding tool, editor extension and AI desktop app installed by you, your employees and your freelancers.
- [ ] For each item, write down where the installer came from (official site, marketplace, link in a message, search ad).
- [ ] Confirm each publisher on the vendor's own website or official marketplace listing, not from a link someone sent you.
- [ ] Remove anything you cannot verify. When unsure, remove it and reinstall from the vendor's own page.
- [ ] If anyone installed a Claude Code-branded extension in Cursor from an unfamiliar publisher, mark that laptop as exposed.
- [ ] On an exposed laptop, check the SSH authorized_keys file and recent logins for keys or sessions nobody can explain.
- [ ] Decide with your IT person whether an exposed laptop is reviewed in place or rebuilt.
- [ ] Rotate credentials stored on any machine you are unsure about, from a clean device: cloud keys, payment API keys, hosting logins, GitHub and GitLab tokens.
- [ ] Record each rotation in a password manager so nothing is missed.
- [ ] Ask your IT provider in writing whether you run GitLab, Cisco ASA/FTD, VMware or exposed Linux servers.
- [ ] Get written confirmation that the October 31 and November 1 fixes are applied, and note the date and who confirmed.
- [ ] For the Linux kernel update: back up or snapshot first, schedule a short window, and reboot to load the new kernel.
- [ ] Adopt an approved AI tools list; new installs need a second person to check them.
- [ ] Add the freelancer security clause to every freelancer or agency contract.

## Worksheet 1: AI tool and extension inventory

Copy one row per item per machine.

| Tool or extension | Machine / owner | Where installed from | Publisher verified (Y/N, how) | Decision (keep / remove / ask) |
|---|---|---|---|---|
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |

Totals: installed ____ | verified ____ | removed ____ | still to check ____

## Worksheet 2: Possibly exposed laptop

- Owner and machine: ______________________
- Extension or app in question: ______________________
- Installed from, and date: ______________________
- Unexplained SSH keys or logins found (Y/N, details): ______________________
- Credentials stored on this machine (list every one): ______________________
- Rotation order (payment and hosting first, then cloud, then repo tokens): ______________________
- Rotated on (date) and by whom: ______________________
- Decision: review in place / rebuild. Decided by: ______________________

## Worksheet 3: Patch confirmation tracker

| Product | Do we run it? (Y/N) | Deadline | Patched on (date) | Confirmed in writing by | Reboot or restart done? |
|---|---|---|---|---|---|
| Linux kernel (CVE-2026-46300) | | Oct 31 | | | |
| GitLab (CVE-2026-97229) | | Nov 1 | | | |
| Cisco ASA/FTD (CVE-2026-76418) | | Nov 1 | | | |
| VMware | | Check the CISA catalog for the date | | | |

## Template: patch confirmation email

```text
Subject: Written confirmation needed by Monday: exploited-vulnerability patching

Hi [name],

Please confirm in writing by [day, time]:

1. Do we run GitLab, Cisco ASA/FTD, VMware, or Linux servers? List each one with its version.
2. For each, has the fix for the exploited vulnerabilities with CISA deadlines of October 31 (Linux kernel, CVE-2026-46300) and November 1 (GitLab, CVE-2026-97229; Cisco ASA/FTD, CVE-2026-76418) been applied? Give the date.
3. For the Linux kernel, has each server been rebooted into the new kernel?
4. What downtime should we expect, and when is the maintenance window?
5. Is there anything you cannot confirm, and why?

If a product is not in use, please say "not in use" rather than leaving it out.

Thanks,
[name]
```

## Template: approved AI tools policy (one page)

```text
AI TOOLS POLICY, [company], effective [date]

1. Install AI coding tools, editor extensions and AI desktop apps only from the vendor's own official website or its official marketplace listing.
2. Never install from a link in an email, chat message or search ad.
3. Approved tools: [list]. Anything not on this list needs approval from [name] before install.
4. Before approving, a second person confirms the publisher name on the vendor's own site.
5. Client and company credentials stay in the password manager and are never saved in plain files on personal machines.
6. If you think you installed a fake tool, tell [name] immediately. Do not wait, and do not try to hide it. Nobody is punished for reporting early.
7. This list is reviewed every [quarter].
```

## Template: freelancer security clause

```text
Security. The Contractor will (a) keep Client credentials, keys and tokens off personal devices and out of unencrypted files, (b) install development tools, editor extensions and AI tools only from the official publisher's website or official marketplace, and (c) notify the Client within 24 hours of discovering or reasonably suspecting a compromise of any device or account that holds Client access. [Have your lawyer review this wording before use.]
```

## AI prompts

Paste your own documents where indicated. If the AI is unsure, it should say so.

```text
Here is a list of editor extensions and apps installed on our team's laptops: [paste list]. For each, tell me what it normally is, who the legitimate publisher should be, and what I should check to confirm this is the real one. Flag anything that looks like a fake AI brand. If you do not recognise an item or are not sure of its publisher, say "unsure" and tell me how to check rather than guessing.
```

```text
A developer on my team installed a Claude Code-branded extension in Cursor and we are not sure it was the official one. Using the details I paste below, give me a step-by-step checklist a non-expert and their IT person can follow to check for a persistent SSH backdoor, and which credentials to rotate first. Where a step depends on something you cannot know, say so.

Operating system and what is stored on the machine: [paste details]
```

```text
I run a small business with [number] people and [number] freelancers who touch our website code. Using the notes I paste below, write a one-page policy on which AI coding extensions and AI desktop apps may be installed, how to verify the publisher, and who approves new ones. Plain language. If you are unsure about a technical step, say so.

Our current practices: [paste notes]
```

## Sources

- https://apprised.news/desk/tech/2026-10-31
- https://www.microsoft.com/en-us/security/blog/2026/10/30/inside-malicious-claude-code-branded-cursor-extension-persistent-ssh-backdoor/
- https://www.darkreading.com/cyberattacks-data-breaches/devs-trojanized-claude-code-extension-cursor
- https://securityaffairs.com/202149/malware/yoba-malware-hides-a-crypto-miner-behind-legitimate-openai-and-anthropic-binaries.html
- https://www.bleepingcomputer.com/news/security/critical-linux-kernel-flaw-allows-remote-root-attacks-on-mptcp-servers/