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TI-2026-66069 Aliases CVE-2026-104426GHSA-g338-vc6m-x872

Zebra before 6.1.0 Quadratic Complexity DoS via Block Transparent Value Check

Priority LOW 35CWE-407Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Attack requirements
Present
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-407.

Summary

Zebra before 6.1.0 contains an inefficient algorithmic complexity vulnerability in remaining_transaction_value that clones the entire block-level spent-UTXO map per transaction during contextual verification. Attackers can mine or seed the mempool with roughly 26,000 minimal single-input transactions in one block, stalling every validating node for over 52 seconds.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00308 23rd percentileScored 2026-11-07
Fix Fixed zebra (ZcashFoundation): 6.1.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
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 6.1.06.1.0Patch availableCNA
  • zebra VendorZcashFoundation Affected before 6.1.0 Fixed in 6.1.0 Patch available CNA

Remediation

  • Fix · CNA zebra (ZcashFoundation) Fixed in 6.1.0

Fixed in the same release

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

  • Release ·

    ZcashFoundation zebra 6.1.0

    4 records Highest priority Priority LOW 4 LOW

    Other records, highest priority first

    • TI-2026-66068 Zebra before 6.1.0 Batch-Verification Poisoning DoS via Unattributed Pushed TransactionsPriority LOW 36
    • TI-2026-66070 Zebra before 6.1.0 Chain Stall via Stale parent_error_map EntryPriority LOW 35
    • TI-2026-66067 Zebra before 6.1.0 Incorrect Block Size Calculation in getblocktemplatePriority LOW 28
    Show all 4 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-104426
  2. 2026-10-03 Alias added: GHSA-g338-vc6m-x872

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