ZcashFoundation Zebra improper following of specification by caller

Summaryinfo

A vulnerability was found in ZcashFoundation Zebra. It has been rated as critical. The affected element is an unknown function. Performing a manipulation results in improper following of specification by caller. This vulnerability was named CVE-2026-41583. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical has been found in ZcashFoundation Zebra (version unknown). This affects an unknown function. The manipulation with an unknown input leads to a improper following of specification by caller vulnerability. CWE is classifying the issue as CWE-573. The product does not follow or incorrectly follows the specifications as required by the implementation language, environment, framework, protocol, or platform. This is going to have an impact on integrity, and availability. The summary by CVE is:

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 upgrade. Zebra nodes could thus accept and eventually mine a block that would be considered invalid by zcashd nodes, creating a consensus split between Zebra and zcashd nodes. In a similar vein, for V4 transactions, Zebra mistakenly used the "canonical" hash type when computing the sighash while zcashd (correctly per the spec) uses the raw value, which could also crate a consensus split. This issue has been patched in zebrad version 4.3.1 and zebra-script version 5.0.2.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-41583 since 04/21/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

Upgrading eliminates this vulnerability.

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Productinfo

Vendor

• ZcashFoundation

Name

• Zebra

Website

• Product: https://github.com/ZcashFoundation/zebra/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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