CVE-2021-27928: A remote code execution issue was discovered in MariaDB 10.2 before 10.2.37, 10.3 before 10.3.28, 10.4 before

Q: How do I fix CVE-2021-27928?

mariadb: upgrade to 10.2.37, 10.3.28, 10.4.18, 10.5.9; percona server: upgrade to newer than 2021-03-03; wsrep: upgrade to newer than 2021-03-03. Exact commands for each OS are on this page.

Q: Is CVE-2021-27928 being exploited?

CVE-2021-27928 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2021-27928 affect?

CVE-2021-27928 affects mariadb, percona server, wsrep. Severity is high (CVSS 7.2). A remote code execution issue was discovered in MariaDB 10.2 before 10.2.37, 10.3 before 10.3.28, 10.4 before 10.4.18, and 10.5 before 10.5.9; Percona Server through 2021-03-03; and the wsrep patch through 2021-03-03 for MySQL. An untrusted

Q: How urgent is CVE-2021-27928?

Priority 60/100. High severity; EPSS top 1%: very likely to be exploited; Public exploit reference; On your watchlist

This week

HIGH 7.2WATCHLISTUPGRADEUPGRADEUPGRADE

CVE-2021-27928 is a high-severity flaw (CVSS 7.2) affecting mariadb, percona server, wsrep. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A remote code execution issue was discovered in MariaDB 10.2 before 10.2.37, 10.3 before 10.3.28, 10.4 before 10.4.18, and 10.5 before 10.5.9; Percona Server through 2021-03-03; and the wsrep patch through 2021-03-03 for MySQL. An untrusted search path leads to eval injection, in which a database SUPER user can execute OS commands after modifying wsrep_provider and wsrep_notify_cmd. NOTE: this does not affect an Oracle product.

Why this priority

High severity
EPSS top 1%: very likely to be exploited
Public exploit reference
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	7.2 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	High
User interaction	None
EPSS exploit chance	38.4% (top 1%)
CISA exploited list	No
Weakness	CWE-94
Published	2021-03-19
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: debian · galeracluster · mariadb · percona

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

Am I affected?

Timeline

2021-03-19 03:15 UTCPublished CVE record published
2026-06-17 03:45 UTCUpdated Record last modified

mariadb mariadb UPGRADE

Affected: >= 10.2 and < 10.2.37 · >= 10.3 and < 10.3.28 · >= 10.4 and < 10.4.18 · >= 10.5 and < 10.5.9

Fixed in: 10.2.37, 10.3.28, 10.4.18, 10.5.9

Safe to downgrade to: a release before 10.2

1. Check installed version

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

2. UPGRADE to 10.2.37 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade mariadb

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 10.2 (Debian / Ubuntu)

apt-cache madison mariadb sudo apt install mariadb=<VERSION_BEFORE_10.2> sudo apt-mark hold mariadb

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

dnf --showduplicates list mariadb sudo dnf downgrade mariadb-<VERSION_BEFORE_10.2> sudo dnf versionlock add mariadb

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.

percona percona server UPGRADE

Affected: <= 2021-03-03

Fixed in: newer than 2021-03-03

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy percona-server || rpm -q percona-server || percona-server --version

2. UPGRADE to newer than 2021-03-03 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade percona-server

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade percona-server

Note

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

galeracluster wsrep UPGRADE

Affected: <= 2021-03-03

Fixed in: newer than 2021-03-03

Safe to downgrade to: no unaffected older release

1. Check installed version

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

2. UPGRADE to newer than 2021-03-03 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade wsrep

Note

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

debian debian linux MITIGATE

Affected: 9.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 9.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

Exploit-DB: MariaDB 10.2 - 'wsrep_provider' OS Command Execution

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-2021-27928?

mariadb: upgrade to 10.2.37, 10.3.28, 10.4.18, 10.5.9; percona server: upgrade to newer than 2021-03-03; wsrep: upgrade to newer than 2021-03-03. Exact commands for each OS are on this page.

Is CVE-2021-27928 being exploited?

CVE-2021-27928 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-2021-27928 affect?

CVE-2021-27928 affects mariadb, percona server, wsrep. Severity is high (CVSS 7.2). A remote code execution issue was discovered in MariaDB 10.2 before 10.2.37, 10.3 before 10.3.28, 10.4 before 10.4.18, and 10.5 before 10.5.9; Percona Server through 2021-03-03; and the wsrep patch through 2021-03-03 for MySQL. An untrusted

How urgent is CVE-2021-27928?

Priority 60/100. High severity; EPSS top 1%: very likely to be exploited; Public exploit reference; On your watchlist

Software pages

MySQL vulnerabilities · MariaDB vulnerabilities · Debian vulnerabilities

Related CVEs

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References

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