CVE-2026-34377

Severity CVSS v4.0:

HIGH

Type:

Unavailable / Other

Publication date:

31/03/2026

Last modified:

06/04/2026

Description

ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.3.0 and zebra-consensus version 5.0.1, a logic error in Zebra&#39;s transaction verification cache could allow a malicious miner to induce a consensus split. By matching a valid transaction&#39;s txid while providing invalid authorization data, 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 would not allow invalid transactions to be accepted but could result in a consensus split between vulnerable Zebra nodes and invulnerable Zebra and Zcashd nodes. This issue has been patched in zebrad version 4.3.0 and zebra-consensus version 5.0.1.

Impact

Vector 4.0

CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:H/SC:N/SI:H/SA:H CVSS v4.0 Severity and Metrics:

Base Score: 8.40 HIGH
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:H/SC:N/SI:H/SA:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Attack Requirements (AT): None
Privileges Required (PR): High
User Interaction (UI): None
Confidentiality (VC): None
Integrity (VI): High
Availability (VA): High
Confidentiality (SC): None
Integrity (SI): High
Availability (SA): High

Base Score 4.0

8.40

Severity 4.0

HIGH

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 8.10 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): High
Availability (A): High