CVE-2026-109366
Zebra before 6.4.0 contains an improper integrity validation vulnerability in the inbound gossip download path that allows unauthenticated peers to force dropping of new blocks without penalty. Attackers can serve a real block with a coinbase scriptSig rewritten to height 1, which keeps the ZIP-244 block hash, triggering a behind-tip drop before consensus validation and delaying tip discovery for mining backends.
Published:Oct 12, 2026
Last Modified:Oct 26, 2026
EPS:Oct 12, 2026
EPSS Score:0.00157
CVSS Score:3.7
Affected Products
Vendor
Product
Action
Vendor
Zcashfoundation
Product
Zebra
Zcashfoundation
Zebra
Vendor
Zfnd
Product
Zebra
Zfnd
Zebra
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
Related CVEs
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
