What is CVE-2019-25005?

CVE-2019-25005 is a high-severity vulnerability in Chacha20 Project, classified under Integer Overflow or Wraparound. CVSS score: 7.5/10. Published 2020-12-31.

How severe is CVE-2019-25005?

High severity. CVSS v3 base score is 7.5 out of 10.

Integer overflow in Chacha20 Project

CVE-2019-25005

An issue was discovered in the chacha20 crate before 0.2.3 for Rust. A ChaCha20 counter overflow makes it easier for attackers to determine plaintext.

Vulnerability class: Integer Overflow

Published 2020-12-31 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.013 (69.8th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 70th percentile — 69.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: +0.000

Affected products

Chacha20 Project

Weakness classification (CWE)

CWE-190 — Integer Overflow or Wraparound

References

rustsec.org/advisories/RUSTSEC-2019-0029.html (Third Party Advisory)

Frequently asked questions

What is CVE-2019-25005?: CVE-2019-25005 is a high-severity vulnerability in Chacha20 Project, classified under Integer Overflow or Wraparound. CVSS score: 7.5/10. Published 2020-12-31.
How severe is CVE-2019-25005?: High severity. CVSS v3 base score is 7.5 out of 10.