CVE-2026-33343: etcd is a distributed key-value store for the data of a distributed system

Routine

NONE 0.0REMOTEUPGRADE

CVE-2026-33343 is a none-severity flaw (CVSS 0.0) affecting etcd. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

etcd is a distributed key-value store for the data of a distributed system. Prior to versions 3.4.42, 3.5.28, and 3.6.9, an authenticated user with RBAC restricted permissions on key ranges can use nested transactions to bypass all key-level authorization. This allows any authenticated user with direct access to etcd to effectively ignore all key range restrictions, accessing the entire etcd data store. Kubernetes does not rely on etcd’s built-in

Why this priority

Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	0.0 (None)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.2% (top 88%)
CISA exploited list	No
Weakness	CWE-863
Published	2026-03-26
Last modified	2026-06-17

Publisher (CNA): GitHub, Inc. · Vendor: etcd

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

Am I affected?

Timeline

2026-03-26 14:16 UTCPublished CVE record published
2026-06-17 10:37 UTCUpdated Record last modified

etcd etcd UPGRADE

Affected: < 3.4.42 · >= 3.5.0 and < 3.5.28 · >= 3.6.0 and < 3.6.9

Fixed in: 3.4.42, 3.5.28, 3.6.9

Safe to downgrade to: a release before 3.5.0

1. Check installed version

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

2. UPGRADE to 3.4.42 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade etcd

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 3.5.0 (Debian / Ubuntu)

apt-cache madison etcd sudo apt install etcd=<VERSION_BEFORE_3.5.0> sudo apt-mark hold etcd

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

dnf --showduplicates list etcd sudo dnf downgrade etcd-<VERSION_BEFORE_3.5.0> sudo dnf versionlock add etcd

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-2026-33343?

etcd: upgrade to 3.4.42, 3.5.28, 3.6.9. Exact commands for each OS are on this page.

Is CVE-2026-33343 being exploited?

CVE-2026-33343 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-2026-33343 affect?

CVE-2026-33343 affects etcd. Severity is none (CVSS 0.0). etcd is a distributed key-value store for the data of a distributed system. Prior to versions 3.4.42, 3.5.28, and 3.6.9, an authenticated user with RBAC restricted permissions on key ranges can use nested transactions to bypass all key-leve

How urgent is CVE-2026-33343?

Priority 8/100. Remotely exploitable, no login, no user action

Software pages

Kubernetes vulnerabilities · etcd vulnerabilities

Related CVEs

CVE-2026-59818 MEDIUM 6.5 UPGRADE etcd is a distributed key-value store for the data of a distributed system
CVE-2026-44283 NONE 0.0 UPGRADE etcd is a distributed key-value store for the data of a distributed system
CVE-2026-33413 HIGH 8.8 UPGRADE etcd is a distributed key-value store for the data of a distributed system

References

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