Medium severity · published Oct 2, 2026
CVE-2026-104429
Zebra before 6.0.0-rc.0 Per-Peer Mempool Admission Bypass via P2P tx Messages
5.3
CVSS
0.3%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 23% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZE
zebra · ZcashFoundation
before 6.0.0-rc.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-104429
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-104429
vendor-advisory
https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-m9xx-8rcj-vmgp
third-party-advisory
https://www.vulncheck.com/advisories/zebra-before-6.0.0-rc.0-per-peer-mempool-admission-bypass-via-p2p-tx-messages
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