What is CVE-2018-20586?

CVE-2018-20586 is a medium-severity vulnerability in Bitcoin Core, classified under Improper Encoding or Escaping of Output. CVSS score: 5.3/10. Published 2020-03-12.

How severe is CVE-2018-20586?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Is CVE-2018-20586 known to be exploited?

3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Bitcoin Core

CVE-2018-20586

bitcoind and Bitcoin-Qt prior to 0.17.1 allow injection of arbitrary data into the debug log via an RPC call.

Published 2020-03-12 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.011 (64.0th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 64th percentile — 64.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000

Affected products

Bitcoin Core — versions 0.12.0, 0.12.1, 0.13

Weakness classification (CWE)

CWE-116 — Improper Encoding or Escaping of Output

Public proof-of-concept exploits

References

en.bitcoin.it/wiki/Common_Vulnerabilities_and_Exposures (Exploit, Vendor Advisory)

Frequently asked questions

What is CVE-2018-20586?: CVE-2018-20586 is a medium-severity vulnerability in Bitcoin Core, classified under Improper Encoding or Escaping of Output. CVSS score: 5.3/10. Published 2020-03-12.
How severe is CVE-2018-20586?: Medium severity. CVSS v3 base score is 5.3 out of 10.
Is CVE-2018-20586 known to be exploited?: 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.