CVE-2026-104423
Zebra before 6.2.1 Denial of Service via Uncapped V6 Shielded Proof Verification
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Description
Zebra (zebrad) before 6.2.1 contains an asymmetric resource consumption vulnerability that allows unauthenticated peers to stall block verification by pushing V6 mempool transactions with invalid Halo2 proofs. Attackers can flood the shared unprioritized Halo2 verification queue with zero-fee transactions carrying zero-filled Orchard and Ironwood proofs, causing nodes to fall behind the chain tip.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
References (2)
SSVC — Action Prioritization
SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.
CVSS
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- NONE
- Integrity
- NONE
- Availability
- HIGH
Quick Info
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