[Help] gvmd NVT feed sync stuck / hash mismatch – unable to start scans

[sgonzalez]

Hello Greenbone community,

I am a new cybersecurity student currently working on a lab assignment where we need to configure GVM on Kali Linux and perform a vulnerability scan (pfSense firewall). Unfortunately, I am unable to get to the scanning stage because my feeds will not complete synchronization.

Here is my situation:

• Environment: Kali Linux VM, latest updates applied.

• Installed and set up GVM following my course video guide.

• I ran the following commands in a split terminal:

  tail -f /var/log/gvm/gvmd.log
  

• 
  greenbone-feed-sync --type GVMD_DATA
  greenbone-feed-sync --type SCAP
  greenbone-feed-sync --type CERT
  
  

• In the GSA web UI, all feeds (GVMD_DATA, SCAP, CERT) show as pending, except NVT, which is Current.

• The logs repeatedly show rebuild attempts and hash mismatches between the scanner and database.

Here is a snippet from my gvmd.log:

md manage:   INFO:2025-09-11 22h32.23 utc:72155: Updating VTs in database ... 206792 new VTs, 0 changed VTs
md manage:WARNING:2025-09-11 22h32.25 utc:72155: update_nvts_from_osp_vts: SHA-256 hash of the VTs in the database (...) does not match the one from the scanner (...)
md   main:MESSAGE:2025-09-11 22h32.25 utc:72155: Rebuilding all NVTs because of a hash value mismatch
...
md manage:   INFO:2025-09-11 22h38.02 utc:73856: OSP service has different VT status (version 202509110701) from database (version 0, 166284 VTs). Starting update ...

Additionally, I saw repeated BACKTRACE entries and messages like:

md manage:MESSAGE:2025-09-11 22h37.47 utc:72155: Received Aborted signal

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What I’ve tried

• Re-running greenbone-feed-sync for each feed type.

• Restarting gvmd and ospd-openvas.

• Verified ownership of /var/lib/gvm and related directories.

• Watching the logs for progress, but it keeps looping with rebuilds.

---

My concern

Because this is for a class assignment, I need to be able to run a scan. Right now, scans aren’t available since the feeds are not in sync. I’m worried I may not be able to complete the lab in time unless I can get my feed status in sync and working.

Any guidance on how to resolve the constant hash mismatch / rebuild loop would be greatly appreciated! Also, I am not very familiar with Kali or other trouble shooting steps, so if you could please, explain things simply if possible.

Thank you,
Shamir

[Eero]

@sgonzalez feed error messages to ai (copilot or chatgpt)

and

This warning and rebuild message from your Greenbone/OpenVAS setup indicates a mismatch between the SHA-256 hash of the Vulnerability Tests (VTs) in the database and those from the scanner. It’s a common issue when the VT cache gets out of sync or corrupted.

Here’s how to fix it:

Step-by-Step Fix for VT Hash Mismatch

1. Stop Services
   Shut down the Greenbone services to avoid interference during the fix:

   sudo systemctl stop gvmd
   sudo systemctl stop ospd-openvas
   

2. Purge the NVT Cache
   Remove the existing NVTs to force a clean rebuild:

   sudo rm -rf /var/lib/openvas/plugins/*
   

3. Resync the NVTs
   Download the latest set of NVTs:

   sudo greenbone-nvt-sync
   

4. Restart Services
   Bring the services back online:

   sudo systemctl start ospd-openvas
   sudo systemctl start gvmd
   

5. Verify the Sync
   Check the logs to confirm that the hash mismatch warning is gone and the database rebuild completes successfully.

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Why This Happens

• The scanner and the database maintain separate VT caches.
• If the sync process is interrupted or corrupted, their hash values diverge.
• Greenbone Manager detects this and triggers a full rebuild to restore consistency⁽¹⁾.

If the issue persists even after these steps, it might indicate a deeper corruption or a version mismatch between components. In that case, updating your Greenbone stack or checking for known bugs in your version might help.

Want help checking your version compatibility or updating your setup?

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[1] Gvmd database rebuild fails/database out of sync (Gvmd database rebuild fails/database out of sync)

Eero