Vulnerability · Published Oct 2, 2026 · Assigned by VulnCheck
CVE-2026-104424Zebra before 6.1.0 Incorrect Block Size Calculation in getblocktemplate
Low 3.7
In plain English
A low-severity security flaw in zebra from ZcashFoundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 20% of all known vulnerabilities).
Severity (CVSS 3.1)3.7Low
Exploit odds (30 days)0.3%top 80.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| ZcashFoundation | zebra | 0 – before 6.1.0 |
Weakness: CWE-131 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
References
- GitHub Security Advisory (GHSA-95m2-vx53-v2jw) vendor-advisory
- VulnCheck Advisory: Zebra before 6.1.0 Incorrect Block Size Calculation in getblocktemplate third-party-advisory