CVE-2026-52739: ZEBRA: Repeated Non-Finalized Shielded Transaction Aborts Zebra Before Duplicate-Nullifier Rejection
ZcashFoundation · zebra
Affected: ZcashFoundation zebra · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 44% of scored CVEs
DescriptionCVE.org
ZEBRA is a Zcash node written entirely in Rust. Prior to 4.5.0, a malicious block producer can terminate zebrad by placing the same shielded transaction in a non-finalized parent block and its child. In zebra-state/src/service/non_finalized_state/chain.rs, Chain::push originally inserted the transaction hash into tx_loc_by_hash and asserted uniqueness before updating shielded data and running the duplicate Sprout, Sapling, or Orchard nullifier checks. The repeated transaction therefore reached the transactions must be unique within a single chain assertion before contextual validation could reject it cleanly. Zebra release builds use panic equals abort, so the reachable assertion terminates the entire process; exploitation requires either two consecutive attacker-mined blocks or an attacker-mined child immediately after an honest block includes the attacker's shielded transaction. This issue is fixed in version 4.5.0.
Affected products2
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- ZcashFoundation · zebra< 4.5.0
- ZcashFoundation · zebra-state< 7.0.0
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Vendor
- ZcashFoundation
- Published
- August 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-52739 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.