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TI-2026-66075 Aliases CVE-2026-104432GHSA-x44x-7hf5-cfvh

Zebra before 6.3.0 False Readiness via Discarded One-Hash FindBlocks Response

Priority LOW 36CWE-754Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
None · None · Low
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

Zebra before 6.3.0 contains an improper exceptional condition check in ChainSync::obtain_tips that discards valid one-hash FindBlocks responses, falsely reporting close-to-tip status. Peers returning only the next block hash cause a zero-length sync sample, making the /ready endpoint return 200 OK while the node remains behind the tip.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00304 23rd percentileScored 2026-11-07
Fix Fixed zebra (ZcashFoundation): 6.3.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ZcashFoundationzebrabefore 6.3.06.3.0Patch availableCNA
  • zebra VendorZcashFoundation Affected before 6.3.0 Fixed in 6.3.0 Patch available CNA

Remediation

  • Fix · CNA zebra (ZcashFoundation) Fixed in 6.3.0

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    ZcashFoundation zebra 6.3.0

    4 records Highest priority Priority MEDIUM 1 MEDIUM, 3 LOW

    Other records, highest priority first

    • TI-2026-66065 Zebra before 6.3.0 Block Sync Denial of Service via Coinbase scriptSig RewritePriority MEDIUM 43
    • TI-2026-66063 Zebra before 6.3.0 Peer Misbehavior Ban Bypass via Gossiped BlocksPriority LOW 36
    • TI-2026-66062 Zebra before 6.3.0 Honest Peer Banning via Far-Ahead FindBlocks HashesPriority LOW 27
    Show all 4 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-104432
  2. 2026-10-03 Alias added: GHSA-x44x-7hf5-cfvh
  3. 2026-10-04 Priority changed: MEDIUM → LOW
  4. 2026-10-06 CISA SSVC decision points changed

References

Advisory 1

  • TI-2026-66079 Zebra before 4.4.0 Consensus Split via SIGHASH_SINGLE Missing-Output Handling CVSS 4.0HIGH 8.3
  • TI-2026-37850 ZEBRA: Mempool transaction admission denial via single-peer inbound queue saturation CVSS 3.1MEDIUM 5.3
  • TI-2026-71182 Improper block validation in Zebra gossip lets peers drop new blocks CVSS 4.0MEDIUM 6.3
  • TI-2026-29537 Zebra: addr/addrv2 Deserialization Resource Exhaustion CVSS 4.0MEDIUM 6.3
  • TI-2026-30136 ZEBRA: Consensus Divergence in Transparent Sighash Hash-Type Handling CVSS 4.0CRITICAL 9.3
  • TI-2026-37853 ZEBRA: Consensus divergence via P2SH sigop undercount in pure-Rust disabled-opcode parser CVSS 4.0CRITICAL 9.3
See all 44 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences