CVE-2026-104421

MediumCVSS 5.3/10Last modified Oct 2, 2026

Description

Zebra before 6.2.1 contains an incomplete cleanup vulnerability that allows unauthenticated peers to block downloading of valid blocks by leaving rejected hashes in SentHashes. Attackers can send a contextually invalid block sharing an honest block's header hash, causing Request::KnownBlock to skip the honest block and keep nodes behind the tip.

Metrics

CVSS 3.1 5.3/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Weakness enumeration

CWE-459

Affected software

No affected versions have been published.

Timeline

Published: Oct 2, 2026
Last modified: Oct 2, 2026
NVD status: Deferred

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