Is CVE-2026-40880 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-40880 being exploited in the wild.

How severe is CVE-2026-40880?

High severity, with a CVSS score of 8.1, published 21 April 2026.

Which products and versions are affected?

zebra-consensus (crates.io) < 5.0.2, SEMVER:introduced=0,fixed=5.0.2; zebrad (crates.io) < 4.3.1, SEMVER:introduced=0,fixed=4.3.1.

Is there a fix for CVE-2026-40880?

Yes. zebra-consensus (crates.io): upgrade to 5.0.2 or later; zebrad (crates.io): upgrade to 4.3.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Am I affected by CVE-2026-40880?

Check whether you run zebra-consensus (crates.io), zebrad (crates.io), Zfnd Zebra-Consensus or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-40880: Zebra: Cached Mempool Verification Bypasses Consensus Rules for Ahead-of-Tip Blocks

Q: Is there a fix for CVE-2026-40880?

Yes. zebra-consensus (crates.io): upgrade to 5.0.2 or later; zebrad (crates.io): upgrade to 4.3.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: Am I affected by CVE-2026-40880?

Check whether you run zebra-consensus (crates.io), zebrad (crates.io), Zfnd Zebra-Consensus or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-40880 · Severity: high · CVSS 8.1 · Published 2026-04-21

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.

Technologies: zebra-consensus (crates.io), zebrad (crates.io), Zfnd Zebrad. Vendors: crates.io, Zfnd.

Quick answers

Is CVE-2026-40880 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-40880 being exploited in the wild.
How severe is CVE-2026-40880?: High severity, with a CVSS score of 8.1, published 21 April 2026.
Which products and versions are affected?: zebra-consensus (crates.io) < 5.0.2, SEMVER:introduced=0,fixed=5.0.2; zebrad (crates.io) < 4.3.1, SEMVER:introduced=0,fixed=4.3.1.
Is there a fix for CVE-2026-40880?: Yes. zebra-consensus (crates.io): upgrade to 5.0.2 or later; zebrad (crates.io): upgrade to 4.3.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2026-40880?: Check whether you run zebra-consensus (crates.io), zebrad (crates.io), Zfnd Zebra-Consensus or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

zebra-consensus (crates.io): upgrade to 5.0.2 or later
```
cargo update -p zebra-consensus
```
zebrad (crates.io): upgrade to 4.3.1 or later
```
cargo update -p zebrad
```

Affected products

zebra-consensus (crates.io) < 5.0.2, SEMVER:introduced=0,fixed=5.0.2
zebrad (crates.io) < 4.3.1, SEMVER:introduced=0,fixed=4.3.1
Zfnd Zebra-Consensus
Zfnd Zebrad

Identifiers

CVE-2026-40880
GHSA-xvj8-ph7x-65gf

References

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