Vulnerability in Z.cash Zcash

CVE-2019-7167

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.

EPSS: 0.017 (74.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2019-7167?
CVE-2019-7167 is a high-severity vulnerability in Z.cash Zcash, classified under Improper Check for Unusual or Exceptional Conditions. CVSS score: 7.5/10. Published 2019-03-27.
How severe is CVE-2019-7167?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2019-7167 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.