CVE-2020-22570: Memcached 1.6.0 before 1.6.3 allows remote attackers to cause a denial of service (daemon crash) via a crafted

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HIGH 7.5REMOTEUPGRADE

CVE-2020-22570 is a high-severity flaw (CVSS 7.5) affecting memcached. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Memcached 1.6.0 before 1.6.3 allows remote attackers to cause a denial of service (daemon crash) via a crafted meta command.

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	1.3% (top 29%)
CISA exploited list	No
Weakness	CWE-77
Published	2023-08-22
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: memcached

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

Am I affected?

Timeline

2023-08-22 19:16 UTCPublished CVE record published
2026-06-17 03:04 UTCUpdated Record last modified

memcached memcached UPGRADE

Affected: >= 1.6.0 and < 1.6.3

Fixed in: 1.6.3

Safe to downgrade to: a release before 1.6.0

1. Check installed version

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

2. UPGRADE to 1.6.3 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade memcached

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 1.6.0 (Debian / Ubuntu)

apt-cache madison memcached sudo apt install memcached=<VERSION_BEFORE_1.6.0> sudo apt-mark hold memcached

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

dnf --showduplicates list memcached sudo dnf downgrade memcached-<VERSION_BEFORE_1.6.0> sudo dnf versionlock add memcached

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-2020-22570?

memcached: upgrade to 1.6.3. Exact commands for each OS are on this page.

Is CVE-2020-22570 being exploited?

CVE-2020-22570 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-2020-22570 affect?

CVE-2020-22570 affects memcached. Severity is high (CVSS 7.5). Memcached 1.6.0 before 1.6.3 allows remote attackers to cause a denial of service (daemon crash) via a crafted meta command.

How urgent is CVE-2020-22570?

Priority 54/100. High severity; Public exploit reference; Remotely exploitable, no login, no user action

Software pages

Memcached vulnerabilities

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References

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