CVE-2026-40880: CWE-1025: Comparison Using Wrong Factors in ZcashFoundation zebrad
ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.3.1 and zebra-consensus version 5.0.2, a logic error in Zebra's transaction verification cache could allow a malicious miner to induce a consensus split. By carefully submitting a transaction that is valid for height H+1 but invalid for H+2 and then mining that transaction in a block at height H+2, a miner could cause vulnerable Zebra nodes to accept an invalid block, leading to a consensus split from the rest of the Zcash network. This vulnerability is fixed in zebrad version 4.3.1 and zebra-consensus version 5.0.2.
AI Analysis
Technical Summary
CVE-2026-40880 is a vulnerability in ZcashFoundation's zebrad node software (versions before 4.3.1) caused by a logic error in the transaction verification cache. This flaw allows a malicious miner to craft and mine a transaction that is valid at one block height but invalid at a subsequent height, leading vulnerable nodes to accept invalid blocks and causing a consensus split from the rest of the Zcash network. The vulnerability is addressed by updates in zebrad 4.3.1 and zebra-consensus 5.0.2.
Potential Impact
If exploited, this vulnerability can cause affected zebrad nodes to accept invalid blocks, resulting in a consensus split from the main Zcash network. This undermines network integrity and could disrupt normal blockchain operations for nodes running vulnerable versions.
Mitigation Recommendations
This vulnerability is fixed in zebrad version 4.3.1 and zebra-consensus version 5.0.2. Users should upgrade to these or later versions to remediate the issue. Patch status is not explicitly stated in the vendor advisory, but the fix is included in these versions.
CVE-2026-40880: CWE-1025: Comparison Using Wrong Factors in ZcashFoundation zebrad
Description
ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.3.1 and zebra-consensus version 5.0.2, a logic error in Zebra's transaction verification cache could allow a malicious miner to induce a consensus split. By carefully submitting a transaction that is valid for height H+1 but invalid for H+2 and then mining that transaction in a block at height H+2, a miner could cause vulnerable Zebra nodes to accept an invalid block, leading to a consensus split from the rest of the Zcash network. This vulnerability is fixed in zebrad version 4.3.1 and zebra-consensus version 5.0.2.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-40880 is a vulnerability in ZcashFoundation's zebrad node software (versions before 4.3.1) caused by a logic error in the transaction verification cache. This flaw allows a malicious miner to craft and mine a transaction that is valid at one block height but invalid at a subsequent height, leading vulnerable nodes to accept invalid blocks and causing a consensus split from the rest of the Zcash network. The vulnerability is addressed by updates in zebrad 4.3.1 and zebra-consensus 5.0.2.
Potential Impact
If exploited, this vulnerability can cause affected zebrad nodes to accept invalid blocks, resulting in a consensus split from the main Zcash network. This undermines network integrity and could disrupt normal blockchain operations for nodes running vulnerable versions.
Mitigation Recommendations
This vulnerability is fixed in zebrad version 4.3.1 and zebra-consensus version 5.0.2. Users should upgrade to these or later versions to remediate the issue. Patch status is not explicitly stated in the vendor advisory, but the fix is included in these versions.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-15T15:57:41.719Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69e7d08b19fe3cd2cdf3fbad
Added to database: 4/21/2026, 7:31:23 PM
Last enriched: 4/21/2026, 7:46:13 PM
Last updated: 4/21/2026, 9:53:43 PM
Views: 5
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