CVE-2026-104421

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Source
https://cve.org/CVERecord?id=CVE-2026-104421
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-104421.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-104421
Aliases
  • GHSA-x93j-mj2f-q338
Published
2026-10-02T11:38:02Z
Modified
2026-10-04T02:45:50Z
Severity
  • 6.9 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N CVSS Calculator
Summary
Zebra before 6.2.1 Block Download Denial of Service via KnownBlock SentHashes Lockout
Details

Zebra before 6.2.1 contains an incomplete cleanup vulnerability that allows unauthenticated peers to block downloading of valid blocks by leaving rejected hashes in SentHashes. Attackers can send a contextually invalid block sharing an honest block's header hash, causing Request::KnownBlock to skip the honest block and keep nodes behind the tip.

Database specific 
{
    "cna_assigner":  "VulnCheck",
    "cwe_ids":  [
        "CWE-459"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/104xxx/CVE-2026-104421.json"
}
References

Affected packages

Git / github.com/zcashfoundation/zebra

Affected ranges

Type
GIT
Repo
https://github.com/zcashfoundation/zebra
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
f3edc40601b4a377693a32c982d4cddf1795fb6f
Database specific
Show details 
{
    "extracted_events":  [
        {
            "introduced":  "0"
        },
        {
            "fixed":  "6.2.1"
        }
    ],
    "source":  [
        "AFFECTED_FIELD",
        "DESCRIPTION"
    ]
}

Affected versions

4.*
4.3.1
tower-batch-control-v1.*
tower-batch-control-v1.1.0
tower-batch-control-v1.1.1
tower-fallback-v0.*
tower-fallback-v0.2.42
tower-fallback-v0.2.43
v1.*
v1.0.0
v1.0.0-alpha.0
v1.0.0-alpha.1
v1.0.0-alpha.10
v1.0.0-alpha.11
v1.0.0-alpha.12
v1.0.0-alpha.13
v1.0.0-alpha.14
v1.0.0-alpha.15
v1.0.0-alpha.16
v1.0.0-alpha.17
v1.0.0-alpha.18
v1.0.0-alpha.19
v1.0.0-alpha.2
v1.0.0-alpha.3
v1.0.0-alpha.4
v1.0.0-alpha.5
v1.0.0-alpha.6
v1.0.0-alpha.7
v1.0.0-alpha.8
v1.0.0-alpha.9
v1.0.0-beta.0
v1.0.0-beta.1
v1.0.0-beta.10
v1.0.0-beta.11
v1.0.0-beta.12
v1.0.0-beta.13
v1.0.0-beta.14
v1.0.0-beta.15
v1.0.0-beta.2
v1.0.0-beta.3
v1.0.0-beta.4
v1.0.0-beta.5
v1.0.0-beta.6
v1.0.0-beta.7
v1.0.0-beta.8
v1.0.0-beta.9
v1.0.0-rc.0
v1.0.0-rc.1
v1.0.0-rc.2
v1.0.0-rc.3
v1.0.0-rc.4
v1.0.0-rc.5
v1.0.0-rc.6
v1.0.0-rc.7
v1.0.0-rc.8
v1.0.0-rc.9
v1.0.1
v1.1.0
v1.2.0
v1.3.0
v1.4.0
v1.5.0
v1.5.1
v1.5.2
v1.6.0
v1.6.1
v1.7.0
v1.8.0
v1.9.0
v2.*
v2.0.0
v2.0.0-rc.0
v2.0.1
v2.1.0
v2.2.0
v2.3.0
v2.4.0
v2.4.2
v2.5.0
v3.*
v3.0.0
v3.0.0-rc.0
v3.1.0
v4.*
v4.0.0
v4.1.0
v4.2.0
v4.3.0
v4.3.1
v4.4.0
v4.4.1
v4.5.0
v4.5.1
v5.*
v5.0.0
v5.1.0
v5.1.1
v5.2.0
v6.*
v6.0.0
v6.0.0-rc.0
v6.1.0
v6.2.0
zebra-chain-v11.*
zebra-chain-v11.1.0
zebra-chain-v11.2.0
zebra-consensus-v11.*
zebra-consensus-v11.0.0
zebra-consensus-v12.*
zebra-consensus-v12.0.0
zebra-consensus-v12.0.1
zebra-network-v10.*
zebra-network-v10.1.0
zebra-network-v10.1.1
zebra-network-v10.2.0
zebra-node-services-v9.*
zebra-node-services-v9.1.0
zebra-node-services-v9.1.1
zebra-rpc-v11.*
zebra-rpc-v11.1.0
zebra-rpc-v12.*
zebra-rpc-v12.0.0
zebra-script-v10.*
zebra-script-v10.1.0
zebra-script-v10.1.1
zebra-state-v10.*
zebra-state-v10.1.0
zebra-state-v11.*
zebra-state-v11.0.0
zebra-state-v11.1.0
zebra-utils-v9.*
zebra-utils-v9.1.0
zebra-utils-v9.1.1

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-104421.json"