All vulnerabilities
CVE-2026-104424GHSA-95m2-vx53-v2jw

Zebra before 6.1.0 Incorrect Block Size Calculation in getblocktemplate

ZcashFoundation zebra
Open in ThreatlineRecord JSON
CVSS
6.3Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.27%Chance of exploitation activity in the next 30 days, higher than 18% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in6.1.0Fixed versionCVE List
Published2 Oct 2026Updated 6 Oct 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

Zebra before 6.1.0 contains an incorrect calculation vulnerability in its ZIP-317 block template selector that omits header and transaction-count size from the block budget. Attackers can place valid selectable transactions in a victim miner's mempool to shape templates into oversized blocks, causing rejection and wasted proof-of-work.

Text from CVE List

Affected versions 2

  • zebraaffected: all versions before 6.1.0CVE List
  • zebraunaffected: 6.1.0CVE List

References 2