Medium severity · published Oct 2, 2026
CVE-2026-104427
Zebra before 6.1.0 Chain Stall via Stale parent_error_map Entry
5.9
CVSS
0.3%
EPSS
No
On KEV
Description
Zebra before 6.1.0 contains an incomplete cleanup vulnerability in the state write task that allows remote unauthenticated peers to stall node synchronization by poisoning parent_error_map. Attackers can deliver a coinbase-malleated block sharing a canonical block's hash before it propagates, causing the next canonical block to be rejected and stalling the node for roughly 2,000 blocks.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 23% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZE
zebra · ZcashFoundation
before 6.1.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-104427
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-104427
vendor-advisory
https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-8gxx-hc65-vv82
third-party-advisory
https://www.vulncheck.com/advisories/zebra-before-6.1.0-chain-stall-via-stale-parent-error-map-entry
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