CVE-2020-15899: Grin 3.0.0 before 4.0.0 has insufficient validation of data related to Mimblewimble.

This week

HIGH 7.5REMOTEUPGRADE

CVE-2020-15899 is a high-severity flaw (CVSS 7.5) affecting grin. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Grin 3.0.0 before 4.0.0 has insufficient validation of data related to Mimblewimble.

Why this priority

High severity
Public exploit reference
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.8% (top 45%)
CISA exploited list	No
Weakness	CWE-345
Published	2020-07-28
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: grin

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

Am I affected?

Timeline

2020-07-28 18:15 UTCPublished CVE record published
2026-06-17 02:57 UTCUpdated Record last modified

grin grin UPGRADE

Affected: >= 3.0.0 and < 4.0.0

Fixed in: 4.0.0

Safe to downgrade to: a release before 3.0.0

1. Check installed version

apt-cache policy grin || rpm -q grin || grin --version

2. UPGRADE to 4.0.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade grin

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade grin

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 3.0.0 (Debian / Ubuntu)

apt-cache madison grin sudo apt install grin=<VERSION_BEFORE_3.0.0> sudo apt-mark hold grin

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

dnf --showduplicates list grin sudo dnf downgrade grin-<VERSION_BEFORE_3.0.0> sudo dnf versionlock add grin

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-2020-15899?

grin: upgrade to 4.0.0. Exact commands for each OS are on this page.

Is CVE-2020-15899 being exploited?

CVE-2020-15899 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-2020-15899 affect?

CVE-2020-15899 affects grin. Severity is high (CVSS 7.5). Grin 3.0.0 before 4.0.0 has insufficient validation of data related to Mimblewimble.

How urgent is CVE-2020-15899?

Priority 50/100. High severity; Public exploit reference; Remotely exploitable, no login, no user action

Related CVEs

CVE-2020-6638 HIGH 7.5 UPGRADE Grin through 2.1.1 has Insufficient Validation.
CVE-2020-12439 MEDIUM 5.3 UPGRADE Grin before 3.1.0 allows attackers to adversely affect availability of data on a Mimblewimble blockchain.
CVE-2019-9195 CRITICAL 9.8 UPGRADE util/src/zip.rs in Grin before 1.0.2 mishandles suspicious files

References

← Back to latest CVEs