Zcash, before the Sapling network upgrade (2018-10-28), had a counterfeiting vulnerability. A key-generation process, during evaluation of polynomials related to a to-be-proven statement, produced certain bypass elements. Availability of these elements allowed a cheating prover to bypass a consistency check, and consequently transform the proof of one statement into an ostensibly valid proof of a different statement, thereby breaking the soundness of the proof system. This misled the original Sprout zk-SNARK verifier into accepting the correctness of a transaction.
Conclusion & alert: CVE-2019-7167 is rated Moderate Risk (52.8/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.51%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-01-05 | 0.69% | 0.51% | -0.18% |
| 2 | 2025-11-21 | 0.29% | 0.69% | +0.40% |
| 3 | 2025-11-18 | — | 0.29% | — |
Full EPSS history (13 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.0 | HIGH |
|
3.9 | 3.6 | [email protected] |
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
| URL | Tags |
|---|---|
| http://fortune.com/2019/02/05/zcash-vulnerability-cryptocurrency/ | Press/Media Coverage Third Party Advisory |
| https://github.com/JinBean/CVE-Extension | |
| https://z.cash/blog/zcash-counterfeiting-vulnerability-successfully-remediated/ | Vendor Advisory |