vulnerability / NVI-00017812 / Revision 1
Zebra: Repeated Non-Finalized Shielded Transaction Aborts Zebra Before Duplicate-Nullifier Rejection
GitHub lists this reviewed advisory for zebra-state, zebrad. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
5.9 medium
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
zebra-state
source listed<= 6.0.0
### Am I affected You are affected if: 1. You run `zebrad` up to and including `v4.4.1`. 2. Your node processes blocks past the checkpoint height (non-finalized state is active). 3. The network has NU5 or later activated. All default configurations are affected. ### Summary `Chain::push` in the non-finalized state updates the transaction-location index (`tx_loc_by_hash`) before it runs the duplicate shielded-nullifier guard. When an invalid child block repeats a shielded transaction from its non-finalized parent, the `assert_eq!(prior_pair, None, "transactions must be unique within a single chain")` fires before the contextual validation that would cleanly reject the duplicate. Under Zebra's `panic = "abort"` release profile, this terminates the entire node process. The block should be rejected with a duplicate-nullifier contextual validation error. Instead, the ordering of index updates within `Chain::push` causes the process to abort. ### Details In `zebra-state/src/service/non_finalized_state/chain.rs:1608-1628`, the block push sequence is: 1. Insert transaction hash into `tx_loc_by_hash` with `assert_eq!` on uniqueness 2. Update transparent outputs and inputs 3. Update
zebrad
source listed<= 4.4.1
### Am I affected You are affected if: 1. You run `zebrad` up to and including `v4.4.1`. 2. Your node processes blocks past the checkpoint height (non-finalized state is active). 3. The network has NU5 or later activated. All default configurations are affected. ### Summary `Chain::push` in the non-finalized state updates the transaction-location index (`tx_loc_by_hash`) before it runs the duplicate shielded-nullifier guard. When an invalid child block repeats a shielded transaction from its non-finalized parent, the `assert_eq!(prior_pair, None, "transactions must be unique within a single chain")` fires before the contextual validation that would cleanly reject the duplicate. Under Zebra's `panic = "abort"` release profile, this terminates the entire node process. The block should be rejected with a duplicate-nullifier contextual validation error. Instead, the ordering of index updates within `Chain::push` causes the process to abort. ### Details In `zebra-state/src/service/non_finalized_state/chain.rs:1608-1628`, the block push sequence is: 1. Insert transaction hash into `tx_loc_by_hash` with `assert_eq!` on uniqueness 2. Update transparent outputs and inputs 3. Update
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-hhm7-qrv5-h4r6 ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
Public revision history
Only published revisions appear here. Routine fetches do not create a material-change event.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.