Zebra zebrad 6.4.0 before 7.0.0 performs quadratic work in the mempool coinbase-maturity check because
Source GCVE Database
Not known to be exploited · CVSS 8.7 High : upgrade to 7.0.0 soon.
Data as of 8 Nov 2026, 06:36 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 8.7 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 7.5 |
- Patch
- Available – fixed in 7.0.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 8 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 7 Nov 2026.
What to do
Upgrade zebra to 7.0.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| ZcashFoundationzebra | Affected
| Fixed in
|
crates.iozebrapkg:cargo/zebraOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, operators should consider limiting connections or rate-limiting transaction submissions from peers to mitigate potential resource exhaustion.
Description
Zebra zebrad versions 6.4.0 up to but not including 7.0.0 contain a vulnerability where the mempool coinbase-maturity check performs quadratic work. This occurs because the function Transaction::coinbase_spend_restriction() rebuilds the transaction's output list repeatedly for each spent outpoint. An attacker can exploit this by sending many unsigned transactions with numerous transparent inputs and outputs, causing excessive CPU usage and pinning verification threads without incurring a misbehavior score.
References
- github.com/ZcashFoundation/zebra/security/advisories/GHSA-7jp4-mq53-4cvq (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-123554 (opens in a new tab)
- github.com/ZcashFoundation/zebra/commit/08743d669b33a19bce2a5d54001bd468c03a196e (opens in a new tab)
- vulncheck.com/advisories/zebra-zebrad-6.4.0-before-7.0.0-denial-of-service-via-mempool-coinbase-maturity-check (opens in a new tab)