CVE-2018-20587: Bitcoin Core 0.12.0 through 0.17.1 and Bitcoin Knots 0.12.0 through 0.17.x before 0.17.1.knots20181229 have In

Routine

MEDIUM 5.5UPGRADEUPGRADE

CVE-2018-20587 is a medium-severity flaw (CVSS 5.5) affecting bitcoin core, bitcoin knots. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Bitcoin Core 0.12.0 through 0.17.1 and Bitcoin Knots 0.12.0 through 0.17.x before 0.17.1.knots20181229 have Incorrect Access Control. Local users can exploit this to steal currency by binding the RPC IPv4 localhost port, and forwarding requests to the IPv6 localhost port.

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	5.5 (Medium)
Attack vector	Local
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.4% (top 71%)
CISA exploited list	No
Published	2019-02-11
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: bitcoin · bitcoinknots

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2019-02-11 12:29 UTCPublished CVE record published
2026-06-17 01:53 UTCUpdated Record last modified

bitcoin bitcoin core UPGRADE

Affected: >= 0.12.0 and <= 0.17.1

Fixed in: newer than 0.17.1

Safe to downgrade to: a release before 0.12.0

1. Check installed version

apt-cache policy bitcoin-core || rpm -q bitcoin-core || bitcoin-core --version

2. UPGRADE to newer than 0.17.1 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade bitcoin-core

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade bitcoin-core

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 0.12.0 (Debian / Ubuntu)

apt-cache madison bitcoin-core sudo apt install bitcoin-core=<VERSION_BEFORE_0.12.0> sudo apt-mark hold bitcoin-core

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list bitcoin-core sudo dnf downgrade bitcoin-core-<VERSION_BEFORE_0.12.0> sudo dnf versionlock add bitcoin-core

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

bitcoinknots bitcoin knots UPGRADE

Affected: >= 0.12.0 and <= 0.17.0

Fixed in: newer than 0.17.0

Safe to downgrade to: a release before 0.12.0

1. Check installed version

apt-cache policy bitcoin-knots || rpm -q bitcoin-knots || bitcoin-knots --version

2. UPGRADE to newer than 0.17.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade bitcoin-knots

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade bitcoin-knots

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 0.12.0 (Debian / Ubuntu)

apt-cache madison bitcoin-knots sudo apt install bitcoin-knots=<VERSION_BEFORE_0.12.0> sudo apt-mark hold bitcoin-knots

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list bitcoin-knots sudo dnf downgrade bitcoin-knots-<VERSION_BEFORE_0.12.0> sudo dnf versionlock add bitcoin-knots

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2018-20587?

bitcoin core: upgrade to newer than 0.17.1; bitcoin knots: upgrade to newer than 0.17.0. Exact commands for each OS are on this page.

Is CVE-2018-20587 being exploited?

CVE-2018-20587 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2018-20587 affect?

CVE-2018-20587 affects bitcoin core, bitcoin knots. Severity is medium (CVSS 5.5). Bitcoin Core 0.12.0 through 0.17.1 and Bitcoin Knots 0.12.0 through 0.17.x before 0.17.1.knots20181229 have Incorrect Access Control. Local users can exploit this to steal currency by binding the RPC IPv4 localhost port, and forwarding requ

How urgent is CVE-2018-20587?

Priority 26/100. No elevated risk signals yet.

Related CVEs

CVE-2025-54605 HIGH 7.5 UPGRADE Bitcoin Core through 29.0 allows Uncontrolled Resource Consumption (issue 2 of 2).
CVE-2025-54604 HIGH 7.5 UPGRADE Bitcoin Core through 29.0 allows Uncontrolled Resource Consumption (issue 1 of 2).
CVE-2025-46598 MEDIUM 5.3 UPGRADE Bitcoin Core through 29.0 allows a denial of service via a crafted transaction.
CVE-2025-46597 HIGH 7.5 UPGRADE Bitcoin Core 0.13.0 through 29.x has an integer overflow.
CVE-2024-55563 MEDIUM 5.3 UPGRADE Bitcoin Core through 27.2 allows transaction-relay jamming via an off-chain protocol attack, a related issue t

References

← Back to latest CVEs