Zebra before 6.3.0 Block Sync Denial of Service via Coinbase scriptSig Rewrite
The block sync download path in Zebra (zebrad) before 6.3.0 reads a block's height from its unvalidated coinbase scriptSig and drops blocks that appear too far behind the tip before consensus validation, without penalizing the supplying peer. Because V5 transaction IDs exclude the scriptSig, a malicious peer can repeatedly serve a canonical block whose coinbase claims height 1 while keeping the requested hash, delaying the node's discovery of the newest block.
CVE-2026-104422
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-104422
zebra
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "ZcashFoundation",
"product": "zebra",
"versions": [
{
"status": "affected",
"version": "0",
"lessThan": "6.3.0",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.3.0",
"versionType": "semver"
}
],
"packageURL": "pkg:cargo/Zebrad",
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-104422
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #8065 · Revision 1
- Added to Heist Feed
- Publisher date