Zebra before 6.0.0-rc.0 Per-Peer Mempool Admission Bypass via P2P tx Messages
Priority LOW 36CWE-770Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · Low
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-770.
Summary
Zebra (zebrad) 5.0.0 before 6.0.0-rc.0 does not apply its per-peer mempool admission cap to transactions received as direct P2P tx messages, because these are queued without the sending peer recorded as their source. A remote inbound peer can push many unique transactions to occupy a disproportionate share of mempool admission slots, crowding out honest peers' transaction relay.
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): 6.0.0-rc.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
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| ZcashFoundation | zebra | before 6.0.0-rc.0 | 6.0.0-rc.0 | Patch available | CNA |
- zebra VendorZcashFoundation Affected before 6.0.0-rc.0 Fixed in 6.0.0-rc.0 Patch available CNA
Remediation
- Fix · CNA zebra (ZcashFoundation) Fixed in 6.0.0-rc.0
Timeline
- 2026-10-02 Threatist record created from CVE-2026-104429
- 2026-10-03 Alias added: GHSA-36m2-g2jj-2c6x
References
More ZcashFoundation vulnerabilities
- 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
Sources
- CVE-2026-104429 · CVE Program
- CVE-2026-104429 · NVD
- FIRST EPSS
- GHSA-36m2-g2jj-2c6x · GitHub Advisory Database · CC BY 4.0
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