All vulnerabilities
CVE-2026-109365GHSA-3c94-hf7p-g5mf

Zebra before 6.4.0 Denial of Service via Same-Hash Forged Block Bodies

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)0.15%Chance of exploitation activity in the next 30 days, higher than 3% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in6.4.0Fixed versionCVE List
Published12 Oct 2026Updated 13 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 6.4.0 contains an uncontrolled resource consumption vulnerability that allows unauthenticated peers to force full proof verification by serving forged block bodies with valid header hashes. Attackers can flip authorizing-only bytes such as a coinbase scriptSig, wasting Sapling, Orchard, and Ironwood proof verification without penalty and stalling sync for 67 seconds.

Text from CVE List

Affected versions 2

  • zebraaffected: all versions before 6.4.0CVE List
  • zebraunaffected: 6.4.0CVE List

References 2