How severe is CVE-2026-34377?

CVE-2026-34377 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.

Is CVE-2026-34377 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34377?

CVE-2026-34377 primarily affects Zfnd Zebra. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-34377?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-34377 have an EU (EUVD) identifier?

Yes. CVE-2026-34377 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17467.

When was CVE-2026-34377 published?

CVE-2026-34377 was published on 2026-03-31 and last updated on 2026-06-17.

CVE-2026-34377

CVE-2026-34377 is a high-severity vulnerability in Zfnd Zebra with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-347.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v4: 8.4
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-17467
Weakness: CWE-347
Affected product: Zfnd Zebra
Published: 2026-03-31
Last modified: 2026-06-17

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's transaction verification cache could allow a malicious miner to induce a consensus split. By matching a valid transaction'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.

Frequently asked questions

What is CVE-2026-34377?: 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's transaction verification cache could allow a malicious miner to induce a consensus split. By matching a valid transaction'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.
How severe is CVE-2026-34377?: CVE-2026-34377 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.
Is CVE-2026-34377 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34377?: CVE-2026-34377 primarily affects Zfnd Zebra. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-34377?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-34377 have an EU (EUVD) identifier?: Yes. CVE-2026-34377 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17467.
When was CVE-2026-34377 published?: CVE-2026-34377 was published on 2026-03-31 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:zfnd:zebra:*:*:*:*:*:rust:*:*
cpe:2.3:a:zfnd:zebra-consensus:*:*:*:*:*:rust:*:*

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