CVE-2026-52735 ZEBRA: Consensus divergence via P2SH sigop undercount in pure-Rust disabled-opcode parser

ZEBRA is a Zcash node written entirely in Rust. Prior to 4.5.0, Zebra can accept a block that zcashd rejects because the P2SH signature-operation counter undercounts redeem scripts containing a disabled opcode followed by signature opcodes. In zebra-script/src/lib.rs, p2shinputsigopcount used the...

CVE-2026-52735 ZEBRA: Consensus divergence via P2SH sigop undercount in pure-Rust disabled-opcode parser

ZEBRA is a Zcash node written entirely in Rust. Prior to 4.5.0, Zebra can accept a block that zcashd rejects because the P2SH signature-operation counter undercounts redeem scripts containing a disabled opcode followed by signature opcodes. In zebra-script/src/lib.rs, p2shinputsigopcount used the...

CVE-2026-52735

Zebra (a Rust-based Zcash node) used a pure-Rust P2SH sigop counter that short-circuited on disabled opcodes like OP_CODESEPARATOR, undercounting sigops compared to zcashd. An attacker without mining power could trigger a chain split by broadcasting P2SH spends with malicious redeem scripts. Fixe...

zebrad has consensus divergence via P2SH sigop undercount in pure-Rust disabled-opcode parser

Am I affected You are affected if: 1. You run any version of zebrad up to and including v4.4.1. 2. Your node validates blocks on mainnet, testnet, or any network where both Zebra and zcashd nodes participate. All default configurations are affected. No feature flags, non-default settings, or...

PT-2026-55471

Name of the Vulnerable Software and Affected Versions Zebra versions prior to 4.4.2 Description Zebra can accept blocks that the zcashd reference implementation rejects due to a discrepancy in how P2SH Pay-to-Script-Hash signature-operation counters handle disabled opcodes. In the...

CVE-2026-44497 ZEBRA: Consensus Divergence in Transparent Sighash Hash-Type Handling due to Stale Buffer

ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.4.0 and prior to zebra-script version 6.0.0, the fix for CVE-2026-41583 introduced a separate issue due to insufficient error handling of the case where the sighash type is invalid, during sighash computation. Instead of...

CVE-2026-44497 ZEBRA: Consensus Divergence in Transparent Sighash Hash-Type Handling due to Stale Buffer

ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.4.0 and prior to zebra-script version 6.0.0, the fix for CVE-2026-41583 introduced a separate issue due to insufficient error handling of the case where the sighash type is invalid, during sighash computation. Instead of...

CVE-2026-41583 ZEBRA: Consensus Divergence in Transparent Sighash Hash-Type Handling

ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.3.1 and prior to zebra-script version 5.0.2, after a refactoring, Zebra failed to validate a consensus rule that restricted the possible values of sighash hash types for V5 transactions which were enabled in the NU5 network...

CVE-2026-41583 ZEBRA: Consensus Divergence in Transparent Sighash Hash-Type Handling

ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.3.1 and prior to zebra-script version 5.0.2, after a refactoring, Zebra failed to validate a consensus rule that restricted the possible values of sighash hash types for V5 transactions which were enabled in the NU5 network...

GHSA-GQ4H-3GRW-2RHV Zebra has Consensus Divergence in Transparent Sighash Hash-Type Handling due to Stale Buffer

CVE-2026-44497: Consensus Divergence in Transparent Sighash Hash-Type Handling due to Stale Buffer Summary The fix for https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-8m29-fpq5-89jj introduced a separate issue due to insuficient error handling of the case where the sighash type ...

Zebra Vulnerable to Consensus Divergence in Transparent Sighash Hash-Type Handling

CVE-2026-41583: Consensus Divergence in Transparent Sighash Hash-Type Handling Summary After a refactoring, Zebra failed to validate a consensus rule that restricted the possible values of sighash hash types for V5 transactions which were enabled in the NU5 network upgrade. Zebra nodes could thus...